Organometallic compound, organic light-emitting device including the same, and electronic apparatus including the organic light-emitting device

ABSTRACT

An organometallic compound represented by Formula 1: 
       M(L 1 ) n1 (L 2 ) n2   Formula 1
         wherein M is a transition metal, L 1  is a ligand represented by Formula 2 as provided herein, n1 is 1, 2, or 3, wherein, when n1 is 2, two L 1  groups are identical to or different from each other, and when n1 is 3, two or more of three L 1  groups are different from each other, L 2  is a monodentate ligand, a bidentate ligand, a tridentate ligand, or a tetradentate ligand, and n2 is 0, 1, 2, 3, or 4, wherein, when n2 is 2 or greater, two or more L 2  groups are identical to or different from each other, and L 1  and L 2  are different from each other.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2020-0089868, filed on Jul. 20, 2020, in the KoreanIntellectual Property Office, and all the benefits accruing therefromunder 35 U.S.C. § 119, the content of which is incorporated by referenceherein in its entirety.

BACKGROUND 1. Field

The present disclosure relates to organometallic compounds, organiclight-emitting devices including the same, and electronic apparatusesincluding the organic light-emitting devices.

2. Description of Related Art

Organic light-emitting devices are self-emission devices, which haveimproved characteristics in terms of viewing angles, response time,brightness, driving voltage, and response speed, and produce full-colorimages.

In an example, an organic light-emitting device includes an anode, acathode, and an organic layer arranged between the anode and thecathode, wherein the organic layer includes an emission layer. A holetransport region may be arranged between the anode and the emissionlayer, and an electron transport region may be arranged between theemission layer and the cathode. Holes provided from the anode may movetoward the emission layer through the hole transport region, andelectrons provided from the cathode may move toward the emission layerthrough the electron transport region. The holes and the electronsrecombine in the emission layer to produce excitons. These excitonstransition from an excited state to a ground state to thereby generatelight.

SUMMARY

Provided are organometallic compounds, organic light-emitting devicesincluding the same, and electronic apparatuses including the organiclight-emitting devices.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments of the disclosure.

According to one aspect of one or more embodiments, there is provided anorganometallic compound represented by Formula 1:

M(L₁)_(n1)(L₂)_(n2)  Formula 1

wherein, in Formula 1,

M is a transition metal,

L₁ is a ligand represented by Formula 2,

n1 is 1, 2, or 3, wherein, when n1 is 2, two L₁ groups are identical toor different from each other, and when n1 is 3, two or more of three L₁groups are different from each other,

L₂ is a monodentate ligand, a bidentate ligand, a tridentate ligand, ora tetradentate ligand,

n2 is 0, 1, 2, 3, or 4, wherein, when n2 is 2 or greater, two or more ofL₂ groups are identical to or different from each other,

L₁ and L₂ are different from each other,

wherein, in Formula 2,

Y₁ and Y₂ are each independently N or C,

ring CY₁ and ring CY₂ are each independently a C₅-C₃₀ carbocyclic groupor a C₁-C₃₀ heterocyclic group,

R₁ and R₂ are each independently hydrogen, deuterium, —F, —Cl, —Br, —I,—SF₅, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidgroup or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀alkylthio group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group,a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —Ge(Q₃)(Q₄)(Q₅),—B(Q₆)(Q₇), —P(═O)(Q₈)(Q₉), or —P(Q₈)(Q₉),

a1 and a2 are each independently an integer from 0 to 20,

b1 and b2 are each independently an integer from 0 to 20, and the sum ofb1 and b2 is 1 or greater,

Z₁ and Z₂ in Formula 2 are each independently a group represented byFormula 3,

wherein, in Formula 3,

Q₅₁ and Q₅₂ are each independently hydrogen, deuterium, —F, a cyanogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₁-C₆₀ alkylthio group, asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group,

Q₅₃ is a substituted or unsubstituted C₆-C₆₀ aryl group, a substitutedor unsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, or a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,

two or more of a plurality of R₁ groups are optionally linked to form aC₅-C₃₀ carbocyclic group that is unsubstituted or substituted with atleast one R_(10a) or a C₁-C₃₀ heterocyclic group that is unsubstitutedor substituted with at least one R_(10a),

two or more of a plurality of R₂ groups are optionally linked togetherto form a C₅-C₃₀ carbocyclic group that is unsubstituted or substitutedwith at least one R_(10a) or a C₁-C₃₀ heterocyclic group that isunsubstituted or substituted with at least one R_(10a),

R_(10a) is the same as described in connection with R₁, provided thatR_(10a) is not hydrogen,

* and *′ in Formula 2 each indicate a binding site to M in Formula 1,

* in Formula 3 indicates a binding site to a neighboring atom,

in Formula 2 and Formula 3, substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₁-C₆₀ alkylthio group, the substituted C₃-C₁₀ cycloalkyl group, thesubstituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, thesubstituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, thesubstituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroarylgroup, the substituted monovalent non-aromatic condensed polycyclicgroup, and the substituted monovalent non-aromatic condensedheteropolycyclic group are each independently:

deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, or a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, ora C₁-C₆₀ alkoxy group, each substituted with deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —N(Q₁₁)(Q₁₂),—Si(Q₁₃)(Q₁₄)(Q₁₅), —Ge(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), —P(═O)(Q₁₈)(Q₁₉),—P(Q₁₈)(Q₁₉), or a combination thereof;

a C₃-C₁₀ cycloalkyl group, a C₁ 1-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,or a monovalent non-aromatic condensed heteropolycyclic group, eachunsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —Ge(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇),—P(═O)(Q₂₈)(Q₂₉), —P(Q₂₈)(Q₂₉), or a combination thereof;

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), —Ge(Q₃₃)(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇),—P(═O)(Q₃₈)(Q₃₉), or —P(Q₃₈)(Q₃₉); or

a combination thereof, and

Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ are each independently:hydrogen; deuterium; —F; —C₁; —Br; —I; a hydroxyl group; a cyano group;a nitro group; an amidino group; a hydrazine group; a hydrazone group; acarboxylic acid group or a salt thereof; a sulfonic acid group or a saltthereof; a phosphoric acid group or a salt thereof; a C₁-C₆₀ alkyl groupunsubstituted or substituted with deuterium, —F, a cyano group, a C₁-C₆₀alkyl group, a C₆-C₆₀ aryl group, a deuterated C₆-C₆₀ aryl group, afluorinated C₆-C₆₀ aryl group, or a combination thereof; a C₂-C₆₀alkenyl group; a C₂-C₆₀ alkynyl group; a C₁-C₆₀ alkoxy group; a C₃-C₁₀cycloalkyl group; a C₁-C₁₀ heterocycloalkyl group; a C₃-C₁₀ cycloalkenylgroup; a C₁-C₁₀ heterocycloalkenyl group; a C₆-C₆₀ aryl group or aC₁-C₆₀ heteroaryl group, each unsubstituted or substituted withdeuterium, —F, a cyano group, a C₁-C₆₀ alkyl group, a deuterated C₁-C₆₀alkyl group, a fluorinated C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, adeuterated C₆-C₆₀ aryl group, a fluorinated C₆-C₆₀ aryl group, or acombination thereof; a C₆-C₆₀ aryloxy group; a C₆-C₆₀ arylthio group; amonovalent non-aromatic condensed polycyclic group; or a monovalentnon-aromatic condensed heteropolycyclic group.

According to an aspect of another embodiment, there is provided anorganic light-emitting device including: a first electrode; a secondelectrode; and an organic layer disposed between the first electrode andthe second electrode and including an emission layer, wherein theorganic layer includes at least one organometallic compound representedby Formula 1.

The at least one organometallic compound may be included in the emissionlayer of the organic layer, and the at least one organometallic compoundincluded in the emission layer may function as a dopant.

According to an aspect of another embodiment, there is provided anelectronic apparatus including the organic light-emitting device.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIGURE which shows a schematic cross-sectional view of an organiclight-emitting device according to one or more embodiments.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawing, wherein likereference numerals refer to like elements throughout. In this regard,the present exemplary embodiments may have different forms and shouldnot be construed as being limited to the descriptions set forth herein.Accordingly, the exemplary embodiments are merely described below, byreferring to the FIGURE, to explain aspects. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list.

It will be understood that when an element is referred to as being “on”another element, it can be directly in contact with the other element orintervening elements may be present therebetween. In contrast, when anelement is referred to as being “directly on” another element, there areno intervening elements present.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers, and/or sections, these elements, components, regions, layers,and/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer, orsection from another element, component, region, layer, or section.Thus, a first element, component, region, layer, or section discussedbelow could be termed a second element, component, region, layer, orsection without departing from the teachings of the present embodiments.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise.

The term “or” means “and/or.” It will be further understood that theterms “comprises” and/or “comprising,” or “includes” and/or “including”when used in this specification, specify the presence of statedfeatures, regions, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, regions, integers, steps, operations, elements,components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this general inventive conceptbelongs. It will be further understood that terms, such as those definedin commonly used dictionaries, should be interpreted as having a meaningthat is consistent with their meaning in the context of the relevant artand the present disclosure, and will not be interpreted in an idealizedor overly formal sense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to a crosssection illustration that is a schematic illustration of one or moreidealized embodiments. As such, variations from the shapes of theillustration as a result, for example, of manufacturing techniquesand/or tolerances, are to be expected. Thus, embodiments describedherein should not be construed as limited to the particular shapes ofregions as illustrated herein but are to include deviations in shapesthat result, for example, from manufacturing. For example, a regionillustrated or described as flat may, typically, have rough and/ornonlinear features. Moreover, sharp angles that are illustrated may berounded. Thus, the regions illustrated in the FIGURE are schematic innature and their shapes are not intended to illustrate the precise shapeof a region and are not intended to limit the scope of the presentclaims.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within +30%, 20%, 10%, 5% of the stated value.

An aspect of the present disclosure provides an organometallic compoundrepresented by Formula 1:

M(L₁)_(n1)(L₂)_(n2)  Formula 1

wherein M in Formula 1 is a transition metal.

In one or more embodiments, M may be a Period 1 transition metal, aPeriod 2 transition metal, or a Period 3 transition metal in thePeriodic Table of Elements.

In one or more embodiments, M may be iridium (Ir), platinum (Pt), osmium(Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), thulium (Tm), or rhodium (Rh).

In one or more embodiments, M may be Ir, Pt, Os, or Rh.

In one or more embodiments, M may be Ir.

In Formula 1, L₁ may be a ligand represented by Formula 2:

wherein Formula 2 is the same as described in the present specification.

In Formula 1, n1 indicates the number of L₁ groups, and may be 1, 2, or3. When n1 is 2, two L₁ groups may be identical to or different fromeach other. When n1 is 3, two or more of three L₁ groups may bedifferent from each other.

In Formula 1, L₂ may be a monodentate ligand, a bidentate ligand, atridentate ligand, or a tetradentate ligand.

In Formula 1, n2 indicates the number of L₂ groups, and may be 0, 1, 2,3, or 4. When n2 is 2 or greater, two or more of L₂ groups may beidentical to or different from each other. For example, n2 may be 1 or2.

In one or more embodiments, in Formula 1, i) M may be Ir, and the sum ofn1 and n2 may be 3, for example, a) n1 may be 1 and n2 may be 2, or b)n1 may be 2 and n2 may be 1; or ii) M may be Pt, and the sum of n1 andn2 may be 2, for example, n1 and n2 each may be 1.

In Formula 1, L₁ and L₂ may be different from each other.

In Formula 1, when n1 is 3, two or more of three L₁ groups may bedifferent from each other, and L₁ and L₂ may be different from eachother. In this regard, the organometallic compound represented byFormula 1 may be a heteroleptic complex.

In Formula 2, Y₁ and Y₂ may each independently be C or N. For example,Y₁ may be N, and Y₂ may be C.

In Formula 2, ring CY₁ and ring CY₂ may each independently a C₅-C₃₀carbocyclic group or a C₁-C₃₀ heterocyclic group.

In one or more embodiments, ring CY₁ and ring CY₂ may each independentlyselected from, i) a first ring, ii) a second ring, iii) a condensed ringin which two or more first rings are condensed with each other, iv) acondensed ring in which two or more second rings are condensed with eachother, or v) a condensed ring in which one or more first rings and oneor more second rings are condensed with each other,

wherein the first ring may be a cyclopentane group, a cyclopentenegroup, a furan group, a thiophene group, a pyrrole group, a silolegroup, a germole group, a phosphole group, a selenophene group, a borolegroup, an oxazole group, an oxadiazole group, an oxatriazole group, athiazole group, a thiadiazole group, a thiatriazole group, a pyrazolegroup, an imidazole group, a triazole group, a tetrazole group, anazasilole group, an azagermole group, an azaphosphole group, anazaselenophene group, or an azaborole group, and

the second ring may be an adamantane group, a norbornane group, anorbornene group, a cyclohexane group, a cyclohexene group, a benzenegroup, a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, or a triazine group.

In one or more embodiments, ring CY₁ and ring CY₂ in Formula 2 may eachindependently be a cyclopentane group, a cyclohexane group, acyclohexene group, a benzene group, a naphthalene group, an anthracenegroup, a phenanthrene group, a triphenylene group, a pyrene group, achrysene group, a 1,2,3,4-tetrahydronaphthalene group, a cyclopentadienegroup, a pyrrole group, a furan group, a thiophene group, a silolegroup, a borole group, a phosphole group, a germole group, a selenophenegroup, an indene group, an indole group, a benzofuran group, abenzothiophene group, a benzosilole group, a benzoborole group, abenzophosphole group, a benzogermole group, a benzoselenophene group, afluorene group, a carbazole group, a dibenzofuran group, adibenzothiophene group, a dibenzosilole group, a dibenzoborole group, adibenzophosphole group, a dibenzogermole group, a dibenzoselenophenegroup, a benzofluorene group, a benzocarbazole group, anaphthobenzofuran group, a naphthobenzothiophene group, anaphthobenzosilole group, a naphthobenzoborole group, anaphthobenzophosphole group, a naphthobenzogermole group, anaphthobenzoselenophene group, a dibenzofluorene group, adibenzocarbazole group, a dinaphthofuran group, a dinaphthothiophenegroup, a dinaphthosilole group, a dinaphthoborole group, adinaphthophosphole group, a dinaphthogermole group, adinaphthoselenophene group, an indenophenanthrene group, anindolophenanthrene group, a phenanthrobenzofuran group, aphenanthrobenzothiophene group, a phenanthrobenzosilole group, aphenanthrobenzoborole group, a phenanthrobenzophosphole group, aphenanthrobenzogermole group, a phenanthrobenzoselenophene group, adibenzothiophene 5-oxide group, a 9H-fluorene-9-one group, adibenzothiophene 5,5-dioxide group, an azaindene group, an azaindolegroup, an azabenzofuran group, an azabenzothiophene group, anazabenzosilole group, an azabenzoborole group, an azabenzophospholegroup, an azabenzogermole group, an azabenzoselenophene group, anazafluorene group, an azacarbazole group, an azadibenzofuran group, anazadibenzothiophene group, an azadibenzosilole group, anazadibenzoborole group, an azadibenzophosphole group, anazadibenzogermole group, an azadibenzoselenophene group, anazabenzofluorene group, an azabenzocarbazole group, anazanaphthobenzofuran group, an azanaphthobenzothiophene group, anazanaphthobenzosilole group, an azanaphthobenzoborole group, anazanaphthobenzophosphole group, an azanaphthobenzogermole group, anazanaphthobenzoselenophene group, an azadibenzofluorene group, anazadibenzocarbazole group, an azadinaphthofuran group, anazadinaphthothiophene group, an azadinaphthosilole group, anazadinaphthoborole group, an azadinaphthophosphole group, anazadinaphthogermole group, an azadinaphthoselenophene group, anazaindenophenanthrene group, an azaindolophenanthrene group, anazaphenanthrobenzofuran group, an azaphenanthrobenzothiophene group, anazaphenanthrobenzosilole group, an azaphenanthrobenzoborole group, anazaphenanthrobenzophosphole group, an azaphenanthrobenzogermole group,an azaphenanthrobenzoselenophene group, an azadibenzothiophene 5-oxidegroup, an aza9H-fluorene-9-one group, an azadibenzothiophene 5,5-dioxidegroup, a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, a triazine group, a quinoline group, an isoquinolinegroup, a quinoxaline group, a quinazoline group, a benzoquinoline group,a benzoisoquinoline group, a benzoquinoxaline group, a benzoquinazolinegroup, a phenanthroline group, a phenanthridine group, a pyrrole group,a pyrazole group, an imidazole group, a triazole group, an oxazolegroup, an isooxazole group, a thiazole group, an isothiazole group, anoxadiazole group, a thiadiazole group, an azasilole group, an azaborolegroup, an azaphosphole group, an azagermole group, an azaselenophenegroup, a benzopyrrole group, a benzopyrazole group, a benzimidazolegroup, a benzoxazole group, a benzisoxazole group, a benzothiazolegroup, a benzisothiazole group, a benzoxadiazole group, abenzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, a5,6,7,8-tetrahydroquinoline group, an adamantane group, a norbornanegroup, a norbornene group, a benzene group condensed with a cyclohexanegroup, or a benzene group condensed with a norbornane group.

In one or more embodiments, ring CY₁ in Formula 2 may be a pyridinegroup, a pyrimidine group, a pyrazine group, a pyridazine group, atriazine group, a quinoline group, an isoquinoline group, a quinoxalinegroup, a quinazoline group, a benzoquinoline group, a benzoisoquinolinegroup, a benzoquinoxaline group, a benzoquinazoline group, aphenanthroline group, a phenanthridine group, a5,6,7,8-tetrahydroisoquinoline group, a 5,6,7,8-tetrahydroquinolinegroup, an azafluorene group, an azacarbazole group, an azadibenzofurangroup, an azadibenzothiophene group, or an azadibenzosilole group.

In one or more embodiments, ring CY₂ in Formula 2 may be a benzenegroup, a naphthalene group, an anthracene group, a phenanthrene group, atriphenylene group, a pyrene group, a chrysene group, a1,2,3,4-tetrahydronaphthalene group, or a group represented by Formula2B:

wherein, in Formula 2B,

X₂ may be O, S, Se, or a moiety including N, C, or Si, and

ring 2B-1 and ring 2B-2 may each independently be a benzene group, anaphthalene group, an anthracene group, a phenanthrene group, atriphenylene group, a pyrene group, a chrysene group, a1,2,3,4-tetrahydronaphthalene group, a pyridine group, a pyrimidinegroup, a pyrazine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a quinoxaline group, aquinazoline group, a benzoquinoline group, a benzoisoquinoline group, abenzoquinoxaline group, a benzoquinazoline group, a phenanthrolinegroup, a phenanthridine group, a 5,6,7,8-tetrahydroisoquinoline group, a5,6,7,8-tetrahydroquinoline group, an indene group, an indole group, abenzofuran group, a benzothiophene group, a benzosilole group, afluorene group, a carbazole group, a dibenzofuran group, adibenzothiophene group, a dibenzosilole group, an azaindene group, anazaindole group, an azabenzofuran group, an azabenzothiophene group, anazabenzosilole group, an azafluorene group, an azacarbazole group, anazadibenzofuran group, an azadibenzothiophene group, or anazadibenzosilole group.

In Formula 2, R₁ and R₂ may each independently be hydrogen, deuterium,—F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, a nitro group,an amino group, an amidino group, a hydrazine group, a hydrazone group,a carboxylic acid group or a salt thereof, a sulfonic acid group or asalt thereof, a phosphoric acid group or a salt thereof, a substitutedor unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstitutedC₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynylgroup, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substitutedor unsubstituted C₁-C₆₀ alkylthio group, a substituted or unsubstitutedC₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —Ge(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇),—P(═O)(Q₈)(Q₉), or —P(Q₈)(Q₉), and Q₁ to Q₉ may each be the same asdescribed in the present specification.

In Formula 2, a1 and a2 indicate the number of R₁ groups and the numberof R₂ groups, respectively, and may each independently be an integerfrom 0 to 20. When a1 is 2 or greater, two or more of R₁ groups may beidentical to or different from each other, and when a2 is 2 or greater,two or more of R₂ groups may be identical to or different from eachother. For example, a1 and a2 may each independently be 0, 1, 2, 3, 4,5, or 6.

In one or more embodiments, R₁ and R₂ in Formula 2 may eachindependently be:

hydrogen, deuterium, —F, or a cyano group;

a C₁-C₂₀ alkyl group unsubstituted or substituted with deuterium, —F, acyano group, a C₃-C₁₀ cycloalkyl group, a deuterated C₃-C₁₀ cycloalkylgroup, a fluorinated C₃-C₁₀ cycloalkyl group, a (C₁-C₂₀ alkyl)C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a deuterated C₁-C₁₀heterocycloalkyl group, a fluorinated C₁-C₁₀ heterocycloalkyl group, a(C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, or a combination thereof;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a phenylgroup, a biphenyl group, a naphthyl group, or a pyridinyl group, eachunsubstituted or substituted with deuterium, —F, a cyano group, a C₁-C₂₀alkyl group, a deuterated C₁-C₂₀ alkyl group, a fluorinated C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a deuterated C₁-C₂₀ alkoxy group, afluorinated C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a deuteratedC₃-C₁₀ cycloalkyl group, a fluorinated C₃-C₁₀ cycloalkyl group, a(C₁-C₂₀ alkyl)C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group,a deuterated C₁-C₁₀ heterocycloalkyl group, a fluorinated C₁-C₁₀heterocycloalkyl group, a (C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, aphenyl group, a deuterated phenyl group, a fluorinated phenyl group, a(C₁-C₂₀ alkyl)phenyl group, a biphenyl group, a deuterated biphenylgroup, a fluorinated biphenyl group, a (C₁-C₂₀ alkyl)biphenyl group, anaphthyl group, a deuterated naphthyl group, a fluorinated naphthylgroup, a (C₁-C₂₀ alkyl)naphthyl group, a pyridinyl group, a deuteratedpyridinyl group, a fluorinated pyridinyl group, a (C₁-C₂₀alkyl)pyridinyl group, or a combination thereof; or

—Si(Q₃)(Q₄)(Q₅) or —Ge(Q₃)(Q₄)(Q₅), and

Q₃ to Q₅ may each independently be:

deuterium;

a C₁-C₆₀ alkyl group unsubstituted or substituted with deuterium, —F, acyano group, a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a deuteratedC₆-C₆₀ aryl group, a fluorinated C₆-C₆₀ aryl group, or a combinationthereof; or

a C₆-C₆₀ aryl group or a C₁-C₆₀ heteroaryl group, each unsubstituted orsubstituted with deuterium, —F, a cyano group, a C₁-C₆₀ alkyl group, adeuterated C₁-C₆₀ alkyl group, a fluorinated C₁-C₆₀ alkyl group, aC₆-C₆₀ aryl group, a deuterated C₆-C₆₀ aryl group, a fluorinated C₆-C₆₀aryl group, or a combination thereof.

In one or more embodiments, at least one R₁ group in the number of a1 inFormula 2 may be: deuterium; —F; a C₁-C₂₀ alkyl group or a C₃-C₁₀cycloalkyl group, each unsubstituted or substituted with deuterium, —F,C₁-C₁₀ alkyl group, or a combination thereof; a group represented by—Si(Q₃a)(Q₄a)(Q₅a); or a group represented by —Ge(Q₃a)(Q₄a)(Q₅a),wherein Q₃a to Q₅a are as defined herein for Q₃ to Q₅, respectively.

In one or more embodiments, at least one R₂ group in the number of a2 inFormula 2 may be: deuterium; —F; or a C₁-C₂₀ alkyl group or a C₃-C₁₀cycloalkyl group, each unsubstituted or substituted with deuterium, —F,a C₁-C₁₀ alkyl group, or a combination thereof.

In one or more embodiments, R₁ and R₂ in Formula 2 may eachindependently be:

-   -   hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano        group, a nitro group, an amino group, an amidino group, a        hydrazine group, a hydrazone group, a carboxylic acid group or a        salt thereof, a sulfonic acid group or a salt thereof, a        phosphoric acid group or a salt thereof, —SF₅, C₁-C₂₀ alkyl        group, a C₂-C₂₀ alkenyl group, a C₁-C₂₀ alkoxy group, or a        C₁-C₂₀ alkylthio group;

a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₁-C₂₀ alkoxy group, ora C₁-C₂₀ alkylthio group, each substituted with deuterium, —F, —CI, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₁₀ alkyl group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group,a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.2]octyl group, a (C₁-C₂₀alkyl)cyclopentyl group, a (C₁-C₂₀ alkyl)cyclohexyl group, a (C₁-C₂₀alkyl)cycloheptyl group, a (C₁-C₂₀ alkyl)cyclooctyl group, a (C₁-C₂₀alkyl)adamantanyl group, a (C₁-C₂₀ alkyl)norbornanyl group, a (C₁-C₂₀alkyl)norbornenyl group, a (C₁-C₂₀ alkyl)cyclopentenyl group, a (C₁-C₂₀alkyl)cyclohexenyl group, a (C₁-C₂₀ alkyl)cycloheptenyl group, a (C₁-C₂₀alkyl)bicyclo[1.1.1]pentyl group, a (C₁-C₂₀ alkyl)bicyclo[2.1.1]hexylgroup, a (C₁-C₂₀ alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a(C₁-C₂₀ alkyl)phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a pyridinyl group, a pyrimidinyl group, or a combinationthereof, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexylgroup, a bicyclo[2.2.2]octyl group, a phenyl group, a (C₁-C₂₀alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranylgroup or azadibenzothiophenyl group, each unsubstituted or substitutedwith deuterium, —F, —CI, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid group or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, adeuterated C₂-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, abicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, abicyclo[2.2.2]octyl group, a (C₁-C₂₀ alkyl)cyclopentyl group, a (C₁-C₂₀alkyl)cyclohexyl group, a (C₁-C₂₀ alkyl)cycloheptyl group, a (C₁-C₂₀alkyl)cyclooctyl group, a (C₁-C₂₀ alkyl)adamantanyl group, a (C₁-C₂₀alkyl)norbornanyl group, a (C₁-C₂₀ alkyl)norbornenyl group, a (C₁-C₂₀alkyl)cyclopentenyl group, a (C₁-C₂₀ alkyl)cyclohexenyl group, a (C₁-C₂₀alkyl)cycloheptenyl group, a (C₁-C₂₀ alkyl)bicyclo[1.1.1]pentyl group, a(C₁-C₂₀ alkyl)bicyclo[2.1.1]hexyl group, a (C₁-C₂₀alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a (C₁-C₂₀ alkyl)phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, or a combination thereof; or

—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —Ge(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇),—P(═O)(Q₈)(Q₉), or —P(Q₈)(Q₉), and

Q₁ to Q₉ may each independently be:

deuterium, —F, a cyano group, —CH₃, —CD₃, —CD₂H, —CDH₂, —CH₂CH₃,—CH₂CD₃, —CH₂CD₂H, —CH₂CDH₂, —CHDCH₃, —CHDCD₂H, —CHDCDH₂, —CHDCD₃,—CD₂CD₃, —CD₂CD₂H, —CD₂CDH₂, —CF₃, —CF₂H, —CFH₂, —CH₂CF₃, —CH₂CF₂H,—CH₂CFH₂, —CHFCH₃, —CHFCF₂H, —CHFCFH₂, —CHFCF₃, —CF₂CF₃, —CF₂CF₂H, or—CF₂CFH₂; or

an n-propyl group, an isopropyl group, an n-butyl group, a sec-butylgroup, an isobutyl group, a tert-butyl group, an n-pentyl group, atert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentylgroup, a 3-pentyl group, a sec-isopentyl group, a phenyl group, anaphthyl group, or a pyridinyl group, each unsubstituted or substitutedwith deuterium, —F, a cyano group, a C₁-C₂₀ alkyl group, a deuteratedC₁-C₂₀ alkyl group, a fluorinated C₁-C₂₀ alkyl group, a phenyl group, adeuterated phenyl group, a fluorinated phenyl group, or a combinationthereof.

In Formula 2, Z₁ and Z₂ may each independently be a group represented byFormula 3:

wherein Formula 3 is the same as described above.

In Formula 2, b1 and b2 indicate the number of Z₁ groups and the numberof Z₂ groups, respectively, and may each independently be an integerfrom 0 to 20. When b1 is 2 or greater, two or more of Z₁ groups may beidentical to or different from each other, and when b2 is 2 or greater,two or more of Z₂ groups may be identical to or different from eachother.

In Formula 2, the sum of b1 and b2 may be 1 or greater (for example, 1,2, 3, or 4). That is, the group represented by Formula 2 may include atleast one of Z₁ and Z₂.

For example, b1 and b2 may each independently be 0, 1, 2, or 3.

In one or more embodiments, in Formula 2,

i) b1 may be 1 or 2, and b2 may be 0;

ii) b1 may be 0, and b2 may be 1 or 2; or

iii) b1 and b2 may each be 1.

In Formula 3, Q₅₁ and Q₅₂ may each independently be hydrogen, deuterium,—F, a cyano group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀ alkylthiogroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromaticcondensed polycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, and Q₅₃ may be asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, or a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

In one or more embodiments, at least one of Q₅₁ and Q₅₂ (for example,both Q₅₁ and Q₅₂) in Formula 3 may each independently be deuterium, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group.

In one or more embodiments, Q₅₁ and Q₅₂ in Formula 3 may eachindependently be:

hydrogen, deuterium, —F, or a cyano group;

a C₁-C₂₀ alkyl group unsubstituted or substituted with deuterium, —F, acyano group, a C₃-C₁₀ cycloalkyl group, a deuterated C₃-C₁₀ cycloalkylgroup, a fluorinated C₃-C₁₀ cycloalkyl group, a (C₁-C₂₀ alkyl)C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a deuterated C₁-C₁₀heterocycloalkyl group, a fluorinated C₁-C₁₀ heterocycloalkyl group, a(C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, or a combination thereof;or

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a phenylgroup, a biphenyl group, a naphthyl group, or a pyridinyl group, eachunsubstituted or substituted with deuterium, —F, a cyano group, a C₁-C₂₀alkyl group, a deuterated C₁-C₂₀ alkyl group, a fluorinated C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a deuterated C₁-C₂₀ alkoxy group, afluorinated C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a deuteratedC₃-C₁₀ cycloalkyl group, a fluorinated C₃-C₁₀ cycloalkyl group, a(C₁-C₂₀ alkyl)C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group,a deuterated C₁-C₁₀ heterocycloalkyl group, a fluorinated C₁-C₁₀heterocycloalkyl group, a (C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, aphenyl group, a deuterated phenyl group, a fluorinated phenyl group, a(C₁-C₂₀ alkyl)phenyl group, a biphenyl group, a deuterated biphenylgroup, a fluorinated biphenyl group, a (C₁-C₂₀ alkyl)biphenyl group, anaphthyl group, a deuterated naphthyl group, a fluorinated naphthylgroup, a (C₁-C₂₀ alkyl)naphthyl group, a pyridinyl group, a deuteratedpyridinyl group, a fluorinated pyridinyl group, a (C₁-C₂₀alkyl)pyridinyl group, or a combination thereof.

In one or more embodiments, each of Q₅₁ and Q₅₂ in Formula 3 may not behydrogen.

In one or more embodiments, at least one of Q₅₁ and Q₅₂ (for example,both Q₅₁ and Q₅₂) in Formula 3 may each independently be:

deuterium; or

a C₁-C₂₀ alkyl group unsubstituted or substituted with deuterium, —F, ora combination thereof.

In one or more embodiments, Q₅₃ in Formula 3 may be a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a phenyl group, a biphenylgroup, a naphthyl group, or a pyridinyl group, each unsubstituted orsubstituted with deuterium, —F, a cyano group, a C₁-C₂₀ alkyl group, adeuterated C₁-C₂₀ alkyl group, a fluorinated C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a deuterated C₁-C₂₀ alkoxy group, a fluorinatedC₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a deuterated C₃-C₁₀cycloalkyl group, a fluorinated C₃-C₁₀ cycloalkyl group, a (C₁-C₂₀alkyl)C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, adeuterated C₁-C₁₀ heterocycloalkyl group, a fluorinated C₁-C₁₀heterocycloalkyl group, a (C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, aphenyl group, a deuterated phenyl group, a fluorinated phenyl group, a(C₁-C₂₀ alkyl)phenyl group, a biphenyl group, a deuterated biphenylgroup, a fluorinated biphenyl group, a (C₁-C₂₀ alkyl)biphenyl group, anaphthyl group, a deuterated naphthyl group, a fluorinated naphthylgroup, a (C₁-C₂₀ alkyl)naphthyl group, a pyridinyl group, a deuteratedpyridinyl group, a fluorinated pyridinyl group, a (C₁-C₂₀alkyl)pyridinyl group, or a combination thereof.

In Formula 2, i) two or more of a plurality of R₁ groups may optionallybe linked together to form a C₅-C₃₀ carbocyclic group that isunsubstituted or substituted with at least one R_(10a) or a C₁-C₃₀heterocyclic group that is unsubstituted or substituted with at leastone R_(10a), or ii) two or more of a plurality of R₂ groups mayoptionally be linked together to form a C₅-C₃₀ carbocyclic group that isunsubstituted or substituted with at least one R_(10a) or a C₁-C₃₀heterocyclic group that is unsubstituted or substituted with at leastone R_(10a).

Here, R_(10a) is the same as described in connection with R₁, providedthat R_(10a) is not hydrogen.

In Formula 2, * and *′ each indicate a binding site to M in Formula 1.

In Formula 3, * indicates a binding site to a neighboring atom.

In one or more embodiments, a group represented by

in Formula 2 may be a group represented by one of Formulae CY1-1 toCY1-42:

wherein, in Formulae CY1-1 to CY1-42,

Y₁ may be the same as described in the present specification,

X₁ may be O, S, Se, or a moiety including N, C, or Si,

*′ indicates a binding site to M in Formula 1, and

* indicates a binding site to ring CY₂ in Formula 2.

In one or more embodiments, a group represented by

in Formula 2 may be a group represented by one of Formulae CY1-10 toCY1-42.

In one or more embodiments, a group represented by

in Formula 2 may be a group represented by one of Formulae CY1(1) toCY1(16) or CY1(1)Z to CY1(38)Z:

wherein, in Formulae CY1(1) to CY1(16) and CY1(1)Z to CY1(38)Z,

Y₁ may be the same as described in the present specification,

R₁₁ to R₁₄ may each be the same as described in connection with R₁,provided that each of R₁₁ to R₁₄ may not be hydrogen,

Z₁ to Z₁₄ may each be the same as described in connection with Z₁,

*′ indicates a binding site to M in Formula 1, and

*″ indicates a binding site to ring CY₂ in Formula 2.

For example, Formulae CY1(1) to CY1(16) and CY1(1)Z to CY1(38)Z maysatisfy:

i) one of Condition 1-1-1 and Condition 1-1-2,

ii) Condition 1-2, or

iii) one of Condition 1-1-1 and Condition 1-1-2, and Condition 1-2:

Condition 1-1-1

R₁₂ is hydrogen;

Condition 1-1-2

R₁₂ is: deuterium; —F; a C₁-C₂₀ alkyl group or a C₃-C₁₀ cycloalkylgroup, each unsubstituted or substituted with deuterium, —F, a C₁-C₁₀alkyl group, or a combination thereof; a group represented by—Si(Q₃)(Q₄)(Q₅); or a group represented by —Ge(Q₃)(Q₄)(Q₅);

Condition 1-2

R₁₃ includes two or more carbon atoms (for example, R₁₃ is a C₂-C₂₀alkyl group, a C₃-C₁₀ cycloalkyl group, a phenyl group, or a biphenylgroup, each unsubstituted or substituted with deuterium, —F, a C₁-C₁₀alkyl group, or a combination thereof).

In one or more embodiments, a group represented by

in Formula 2 may be a group represented by one of Formulae CY2-1 toCY2-64:

wherein, in Formulae CY2-1 to CY2-64,

Y₂ may be the same as described in the present specification,

X₂ and X_(2a) may each independently be O, S, Se, or a moiety includingN, C, or Si,

* in Formulae CY2-1 to CY2-14 indicates a binding site to M in Formula1,

*″ in Formulae CY2-1 to CY2-14 indicates a binding site to ring CY₁ inFormula 2, and

Formulae CY2-15 to CY2-64 may satisfy one of Condition 2-1 to Condition2-6:

Condition 2-1:

A₁ is Y₂,

A₂ indicates a binding site to ring CY₁ in Formula 2, and

A₃ and A₄ are each independently N or C;

Condition 2-2:

A₂ is Y₂,

A₃ indicates a binding site to ring CY₁ in Formula 2, and

A₁ and A₄ are each independently N or C;

Condition 2-3:

A₃ is Y₂,

A₄ indicates a binding site to ring CY₁ in Formula 2, and

A₁ and A₂ are each independently N or C;

Condition 2-4:

A₄ is Y₂,

A₃ indicates a binding site to ring CY₁ in Formula 2, and

A₁ and A₂ are each independently N or C;

Condition 2-5:

A₃ is Y₂,

A₂ indicates a binding site to ring CY₁ in Formula 2, and

A₁ and A₄ are each independently N or C;

Condition 2-6:

A₂ is Y₂,

A₁ indicates a binding site to ring CY₁ in Formula 2, and

A₃ and A₄ are each independently N or C.

In one or more embodiments, a group represented by

in Formula 2 may be a group represented by one of Formulae CY2-6 toCY2-14 and CY2-23 to CY2-64.

In one or more embodiments, a group represented by

in Formula 2 may be a group represented by one of Formulae CY2(1) toCY2(96) and CY2(1)Z to CY2(54)Z:

wherein, in Formulae CY2(1) to CY2(96) and CY2(1)Z to CY2(54)Z,

Y₂ may be the same as described in the present specification,

X₂₂ may be C(R_(29a))(R_(29b)), N(R_(29a)), O, S, Se, orSi(R_(29a))(R_(29b)),

R21 to R28, R_(29a), and R_(29b) may each be the same as described inconnection with R₂, and each of R₂₁ to R₂₈ may not be hydrogen,

Z₂₁ to Z₂₈ may each be the same as described in connection with Z₂,

* indicates a binding site to M in Formula 1, and

*″ indicates a binding site to ring CY1 in Formula 2.

In one or more embodiments, L₁ in Formula 1 may include deuterium, afluoro group (—F), a group represented by Si(Q₃)(Q₄)(Q₅), a grouprepresented by —Ge(Q₃)(Q₄)(Q₅), or a combination thereof.

In one or more embodiments, L₂ in Formula 1 may be a group representedby one of Formulae 4A to 4F:

wherein, in Formulae 4A to 4F,

Y₁₃ may be O, N, N(R₃), P(R₃)(R₄), or As(R₃)(R₄),

Y₁₄ may be O, N, N(R₅), P(R₅)(R₆), or As(R₅)(R₆),

T₁₁ may be a single bond, a double bond, *—C(R₃₁)(R₃₂)—*′,*—C(R₃₁)═C(R₃₂)—*′, *═C(R₃₁)—*′, *—C(R₃₁)═*′, *═C(R₃₁)—C(R₃₂)═C(R₃₃)—*′,*—C(R₃₁)═C(R₃₂)—C(R₃₃)═*′, *—N(R₃₁)—*′, or a C₅-C₃₀ carbocyclic groupunsubstituted or substituted with at least one R₃₁,

d₁₁ may be an integer from 1 to 10, wherein, when d₁₁ is 2 or greater,two or more of T₁₁ groups may be identical to or different from eachother,

Y₃ and Y₄ may each independently be C or N,

T₂₁ may be a single bond, a double bond, O, S, Se, C(R₅)(R₆),Si(R₅)(R₆), or N(R₅),

ring CY₃ and ring CY₄ may each independently be a C₅-C₃₀ carbocyclicgroup or a C₁-C₃₀ heterocyclic group,

A₁ may be P or As,

R₃ to R₆ and R₃₁ to R₃₃ may each be the same as described in connectionwith R₁,

a3 and a4 may each independently be an integer from 0 to 20, and

* and *′ each indicate a binding site to M in Formula 1.

For example, L₂ in Formula 1 may be a group represented by Formula 4D.

In one or more embodiments, Y₃, Y₄, ring CY₃, ring CY₄, R₃, R₄, a3, anda4 in Formulae 4C and/or 4D may each be the same as described inconnection with Y₁, Y₂, ring CY1, ring CY₂, R₁, R₂, a1, and a2 inFormula 2, respectively.

In one or more embodiments, in Formula 4D, Y₃ may be N, and Y₄ may be C.

In one or more embodiments, in Formula 4D, T₂₁ may be a single bond.

In one or more embodiments, at least one of R₃ groups in the number ofa3 in Formula 4D may be: deuterium; —F; a C₁-C₂₀ alkyl group or a C₃-C₁₀cycloalkyl group, each unsubstituted or substituted with deuterium, —F,C₁-C₁₀ alkyl group, or a combination thereof; a group represented by—Si(Q₃)(Q₄)(Q₅); or a group represented by —Ge(Q₃)(Q₄)(Q₅), wherein Q₃to Q₅ are defined the same as Q₃ to Q₅ occurred in the definition of R₁and R₂ in Formula 2.

In one or more embodiments, at least one of R₄ groups in the number ofa4 in Formulae 4C and 4D may be: deuterium; —F; or a C₁-C₂₀ alkyl groupor a C₃-C₁₀ cycloalkyl group, each unsubstituted or substituted withdeuterium, —F, a C₁-C₁₀ alkyl group, or a combination thereof.

In one or more embodiments, a group represented by

in Formula 4D may be a group represented by one of Formulae CY3-1 toCY3-42:

wherein, in Formulae CY3-1 to CY3-42,

Y₃ may be the same as described in the present specification,

X₃ may be O, S, Se, or a moiety including N, C, or Si,

* indicates a binding site to M in Formula 1, and

*″ indicates a binding site to T₂₁ in Formula 4D.

In one or more embodiments, a group represented by

in Formula 4D may be a group represented by one of Formulae CY3-10 toCY3-42.

In one or more embodiments, a group represented by

in Formula 4D may be a group represented by one of Formulae CY3(1) toCY3(16):

wherein, in Formulae CY3(1) to CY3(16),

Y₃ may be the same as described in the present specification,

R₃₁ to R₃₄ may each be the same as described in connection with R₃,provided that each of R₃₁ to R₃₄ may not be hydrogen,

* indicates a binding site to M in Formula 1, and

*″ indicates a binding site to T₂₁ in Formula 4D.

For example, Formulae CY3(1) to CY3(16) may satisfy:

i) one of Condition 3-1-1 and Condition 3-1-2,

ii) Condition 3-2, or

iii) one of Condition 3-1-1 and Condition 3-1-2 as well as Condition3-2:

Condition 3-1-1:

R₃₂ is hydrogen;

Condition 3-1-2:

R₃₂ is deuterium; —F; a C₁-C₂₀ alkyl group or a C₃-C₁₀ cycloalkyl group,each unsubstituted or substituted with deuterium, —F, a C₁-C₁₀ alkylgroup, or a combination thereof; a group represented by —Si(Q₃)(Q₄)(Q₅);or a group represented by —Ge(Q₃)(Q₄)(Q₅), wherein Q₃ to Q₅ are definedthe same as Q₃ to Q₅ occurred in the deficition of R₃;

Condition 3-2:

R₃₃ includes two or more carbon atoms (for example, R₃₃ is a C₂-C₂₀alkyl group, a C₃-C₁₀ cycloalkyl group, a phenyl group, or a biphenylgroup, each unsubstituted or substituted with deuterium, —F, a C₁-C₁₀alkyl group, or a combination thereof).

In one or more embodiments, a group represented by

in Formulae 4C and 4D may be a group represented by one of FormulaeCY4-1 to CY4-14, or may be a group represented by one of Formulae CY2-15to CY2-64 that satisfy one of Condition 4-1 to Condition 4-6:

wherein, in Formulae CY4-1 to CY4-14,

Y₄ may be the same as described in the present specification,

X₂ and X_(2a) may each independently be O, S, Se, or a moiety includingN, C, or Si,

*′ in Formulae CY4-1 to CY4-14 indicates a binding site to M in Formula1,

*″ in Formulae CY4-1 to CY4-14 indicates a binding site to a neighboringatom in Formula 4C or a binding site to T₂₁ in Formula 4D, and

Condition 4-1 to Condition 4-6 are as follows:

Condition 4-1:

A₁ is Y₄,

A₂ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D, and

A₃ and A₄ are each independently N or C;

Condition 4-2:

A₂ is Y₄,

A₃ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D, and

A₁ and A₄ are each independently N or C

Condition 4-3:

A₃ is Y₄,

A₄ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D, and

A₁ and A₂ are each independently N or C;

Condition 4-4:

A₄ is Y₄,

A₃ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D, and

A₁ and A₂ are each independently N or C;

Condition 4-5:

A₃ is Y₄,

A₂ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D, and

A₁ and A₄ are each independently N or C;

Condition 4-6:

A₂ is Y₄,

A₁ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D, and

A₃ and A₄ are each independently N or C.

In one or more embodiments, a group represented by

in Formulae 4C and 4D may be a group represented by one of FormulaeCY4-6 to CY4-14, or may be a group represented by one of Formulae CY2-23to CY2-64 that satisfy one of Condition 4-1 to Condition 4-6.

In one or more embodiments, a group represented by

in Formula 4D may be a group represented by one of Formulae CY4(1) toCY4(96):

wherein, in Formulae CY4(1) to CY4(96),

Y₄ may be the same as described in the present specification,

X₄₂ may be C(R_(49a))(R_(49b)), N(R_(49a)), O, S, Se, orSi(R_(49a))(R_(49b)),

R₄₁ to R₄₈, R_(49a), and R_(49b) are each the same as described inconnection with R₄, and each of R₄₁ to R₄₈ may not be hydrogen,

*′ indicates a binding site to M in Formula 1, and

*″ indicates a binding site to a neighboring atom in Formula 4C or abinding site to T₂₁ in Formula 4D.

In one or more embodiments, L₂ in Formula 1 may include deuterium, afluoro group (—F), a group represented by —Si(Q₃)(Q₄)(Q₅), a grouprepresented by —Ge(Q₃)(Q₄)(Q₅), or a combination thereof.

In one or more embodiments, R₁ and R₂ in Formula 2 and R₃ to R₆ and R₃₁to R₃₃ in Formulae 4A to 4F may each independently be hydrogen,deuterium, —F, a cyano group, a nitro group, —SF₅, —CH₃, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, —OCH₃, —OCDH₂, —OCD₂H, —OCD₃, —SCH₃, —SCDH₂,—SCD₂H, —SCD₃, a group represented by one of Formulae 9-1 to 9-39, agroup represented by one of Formulae 9-1 to 9-39 in which at least onehydrogen is substituted with deuterium, a group represented by one ofFormulae 9-1 to 9-39 in which at least one hydrogen is substituted with—F, a group represented by one of Formulae 9-201 to 9-233, a grouprepresented by one of Formulae 9-201 to 9-233 in which at least onehydrogen is substituted with deuterium, a group represented by one ofFormulae 9-201 to 9-233 in which at least one hydrogen is substitutedwith —F, a group represented by one of Formulae 10-1 to 10-132, a grouprepresented by one of Formulae 10-1 to 10-132 in which at least onehydrogen is substituted with deuterium, a group represented by one ofFormulae 10-1 to 10-132 in which at least one hydrogen is substitutedwith —F, a group represented by one of Formulae 10-201 to 10-353, agroup represented by one of Formulae 10-201 to 10-353 in which at leastone hydrogen is substituted with deuterium, a group represented by oneof Formulae 10-201 to 10-353 in which at least one hydrogen issubstituted with —F, —Si(Q₃)(Q₄)(Q₅), or —Ge(Q₃)(Q₄)(Q₅) (wherein Q₁ toQ₅ may each be the same as described in the present specification).

In one or more embodiments, Q₅₁ and Q₅₂ in Formula 3 may eachindependently be hydrogen, deuterium, —F—, a cyano group, —CH₃, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a group represented by one of Formulae9-1 to 9-39, a group represented by one of Formulae 9-1 to 9-39 in whichat least one hydrogen is substituted with deuterium, a group representedby one of Formulae 9-1 to 9-39 in which at least one hydrogen issubstituted with —F, a group represented by one of Formulae 9-201 to9-233, a group represented by one of Formulae 9-201 to 9-233 in which atleast one hydrogen is substituted with deuterium, a group represented byone of Formulae 9-201 to 9-233 in which at least one hydrogen issubstituted with —F, a group represented by one of Formulae 10-1 to10-132, a group represented by one of Formulae 10-1 to 10-132 in whichat least one hydrogen is substituted with deuterium, a group representedby one of Formulae 10-1 to 10-132 in which at least one hydrogen issubstituted with —F, a group represented by one of Formulae 10-201 to10-353, a group represented by one of Formulae 10-201 to 10-353 in whichat least one hydrogen is substituted with deuterium, or a grouprepresented by one of Formulae 10-201 to 10-353 in which at least onehydrogen is substituted with —F.

In one or more embodiments, at least one of Q₅₁ and Q₅₂ (for example,both Q₅₁ and Q₅₂) in Formula 3 may each independently be deuterium, —F—,a cyano group, —CH₃, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a grouprepresented by one of Formulae 9-1 to 9-39, a group represented by oneof Formulae 9-1 to 9-39 in which at least one hydrogen is substitutedwith deuterium, or a group represented by one of Formulae 9-1 to 9-39 inwhich at least one hydrogen is substituted with —F.

In one or more embodiments, Q₅₃ in Formula 3 may be a group representedby one of Formulae 10-12 to 10-132, a group represented by one ofFormulae 10-12 to 10-132 in which at least one hydrogen is substitutedwith deuterium, a group represented by one of Formulae 10-12 to 10-132in which at least one hydrogen is substituted with —F, a grouprepresented by one of Formulae 10-201 to 10-353, a group represented byone of Formulae 10-201 to 10-353 in which at least one hydrogen issubstituted with deuterium, or a group represented by one of Formulae10-201 to 10-353 in which at least one hydrogen is substituted with —F:

wherein, in Formulae 9-1 to 9-39, 9-201 to 9-233, 10-1 to 10-132, and10-201 to 10-353, * indicates a binding site to a neighboring atom, Phis a phenyl group, TMS is a trimethylsilyl group, and TMG is atrimethylgermyl group.

The “group represented by one of Formulae 9-1 to 9-39 in which at leastone hydrogen is substituted with deuterium” and the “group representedby one of Formulae 9-201 to 9-233 in which at least one hydrogen issubstituted with deuterium” may be, for example, a group represented byone of Formulae 9-501 to 9-514 and 9-601 to 9-635:

The “group represented by one of Formulae 9-1 to 9-39 in which at leastone hydrogen is substituted with —F” and the “group represented by oneof Formulae 9-201 to 9-233 in which at least one hydrogen is substitutedwith —F” may be, for example, a group represented by one of Formulae9-701 to 9-710:

The “group represented by one of Formulae 10-1 to 10-132 in which atleast one hydrogen is substituted with deuterium” and the “grouprepresented by one of Formulae 10-201 to 10-353 in which at least onehydrogen is substituted with deuterium” may be, for example, a grouprepresented by one of Formulae 10-501 to 10-553:

The “group represented by one of Formulae 10-1 to 10-132 in which atleast one hydrogen is substituted with —F” and the “group represented byone of Formulae 10-201 to 10-353 in which at least one hydrogen issubstituted with —F” may be, for example, a group represented by one ofFormulae 10-601 to 10-620:

In one or more embodiments, the organometallic compound represented byFormula 1 may be one of Compounds 1 to 2560:

In Formula 1, L₁ may be a ligand represented by Formula 2, and n1 may be1, 2, or 3, wherein, when n1 is 3, two or more of three L₁ groups may bedifferent from each other. In addition, n2 which indicates the number ofL₂ groups in Formula 1 may 0, 1, 2, 3 or 4. Here, L₁ and L₂ may bedifferent from each other. That is, the organometallic compoundrepresented by Formula 1 may be a heteroleptic complex including atleast one ligand represented by Formula 2.

Furthermore, Z₁ and Z₂ in Formula 2 may each be a group represented byFormula 3, Q₅₁ to Q₅₃ in Formula 3 may each be bonded to a carbon atom,Q₅₃ in Formula 3 may be a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, and the sum of b1 and b2,which indicate the number of Z₁ groups and the number of Z₂ groups,respectively, may be 1 or more. That is, the ligand represented byFormula 2 may include at least one group represented by Formula 3.

Accordingly, the organometallic compound represented by Formula 1 mayhave excellent thermal and/or electrical stability, and improvedorientation characteristics, so that an electronic device, such as anorganic light-emitting device, including the organometallic compoundrepresented by Formula 1 may have excellent luminescence efficiencyand/or lifespan characteristics.

The highest occupied molecular orbital (HOMO) energy level, lowestunoccupied molecular orbital (LUMO) energy level, Si energy level, andT₁ energy level of some compounds of the organometallic compoundrepresented by Formula 1 are evaluated using the Gaussian 09 programwith the molecular structure optimization obtained by B3LYP-baseddensity functional theory (DFT), and results thereof are shown inTable 1. The energy levels are in electron volts (eV).

TABLE 1 Compound No. HOMO (eV) LUMO (eV) S₁ (eV) T₁ (eV) 361 −4.777−1.201 2.872 2.514 716 −4.705 −1.172 2.848 2.497 771 −4.791 −1.220 2.8782.533 1653 −4.664 −1.078 2.861 2.519 1693 −4.700 −1.100 2.875 2.520

From Table 1, it is confirmed that the organometallic compoundrepresented by Formula 1 has such electric characteristics that aresuitable for use as a dopant for an electronic device, for example, anorganic light-emitting device.

Synthesis methods of the organometallic compound represented by Formula1 may be recognizable by one of ordinary skill in the art by referringto Synthesis Examples provided below.

Accordingly, the organometallic compound represented by Formula 1 may besuitable for use as a material for forming an organic layer of anorganic light-emitting device, for example, a dopant in an emissionlayer of an organic layer. Thus, another aspect of the presentdisclosure provides an organic light-emitting device including: a firstelectrode; a second electrode; and an organic layer arranged between thefirst electrode and the second electrode and including an emissionlayer, wherein the organic layer includes at least one organometalliccompound represented by Formula 1.

The organic light-emitting device may have, due to the inclusion of anorganic layer including the organometallic compound represented byFormula 1, high external quantum efficiency and long lifespancharacteristics.

The organometallic compound of Formula 1 may be used between a pair ofelectrodes of the organic light-emitting device. For example, theorganometallic compound represented by Formula 1 may be included in theemission layer. In this regard, the organometallic compound may functionas a dopant, and the emission layer may further include a host (wherein,an amount of the organometallic compound represented by Formula 1 issmaller than that of the host). The emission layer may emit, forexample, green light or blue light.

The expression “(an organic layer) includes at least one oforganometallic compound” as used herein may include a case in which “(anorganic layer) includes identical organometallic compounds representedby Formula 1” and a case in which “(an organic layer) includes two ormore different organometallic compounds represented by Formula 1”.

In one or more embodiments, the organic layer may include, as theorganometallic compound, only Compound 1. In this embodiment, Compound 1may be included in the emission layer of the organic light-emittingdevice. In one or more embodiments, the organic layer may include, asthe organometallic compound, Compound 1, and Compound 2. In thisembodiment, Compound 1 and Compound 2 may exist in an identical layer(for example, Compound 1 and Compound 2 all may exist in an emissionlayer).

In one or more embodiments, the first electrode may be an anode, whichis a hole injection electrode, and the second electrode may be acathode, which is an electron injection electrode. In one or moreembodiments, the first electrode may be a cathode, which is an electroninjection electrode, and the second electrode may be an anode, which isa hole injection electrode.

For example, in the organic light-emitting device, the first electrodemay be an anode, and the second electrode may be a cathode, and theorganic layer may further include a hole transport region disposedbetween the first electrode and the emission layer and an electrontransport region disposed between the emission layer and the secondelectrode, wherein and the hole transport region may include a holeinjection layer, a hole transport layer, an electron blocking layer, abuffer layer, or a combination thereof, and the electron transportregion may include a hole blocking layer, an electron transport layer,an electron injection layer, or a combination thereof.

The term “organic layer” as used herein refers to a single layer and/ora plurality of layers between the first electrode and the secondelectrode of the organic light-emitting device. The “organic layer” mayinclude, in addition to an organic compound, an organometallic complexincluding metal.

FIG. is a schematic cross-sectional view of an organic light-emittingdevice 10 according to one or more embodiments. Hereinafter, a structureof an organic light-emitting device according to an embodiment of thepresent disclosure and a method of manufacturing an organiclight-emitting device according to one or more embodiments of thepresent disclosure will be described in connection with the FIGURE. Theorganic light-emitting device 10 includes a first electrode 11, anorganic layer 15, and a second electrode 19, which are sequentiallystacked.

A substrate may be additionally arranged under the first electrode 11 orabove the second electrode 19. For use as the substrate, any substratethat is used in organic light-emitting devices available in the art maybe used, and the substrate may be a glass substrate or a transparentplastic substrate, each having excellent mechanical strength, thermalstability, transparency, surface smoothness, ease of handling, and waterresistance.

The first electrode 11 may be, for example, formed by depositing orsputtering a material for forming the first electrode 11 on thesubstrate. The first electrode 11 may be an anode. The material forforming the first electrode 11 may include materials with a high workfunction to facilitate hole injection. The first electrode 11 may be areflective electrode, a semi-transmissive electrode, or a transmissiveelectrode. In one or more embodiments, the material for forming thefirst electrode 11 may be indium tin oxide (ITO), indium zinc oxide(IZO), tin oxide (SnO₂), or zinc oxide (ZnO). In one or moreembodiments, the material for forming the first electrode 11 may bemetal, such as magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li),calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag).

The first electrode 11 may have a single-layered structure or amulti-layered structure including two or more layers. For example, thefirst electrode 11 may have a three-layered structure of ITO/Ag/ITO.

The organic layer 15 is arranged on the first electrode 11.

The organic layer 15 may include: a hole transport region; an emissionlayer; and an electron transport region.

The hole transport region may be disposed between the first electrode 11and the emission layer.

The hole transport region may include a hole injection layer, a holetransport layer, an electron blocking layer, a buffer layer, or acombination thereof.

The hole transport region may include only either a hole injection layeror a hole transport layer. For example, the hole transport region mayhave a hole injection layer/hole transport layer structure or a holeinjection layer/hole transport layer/electron blocking layer structure,wherein, for each structure, each layer is sequentially stacked on thefirst electrode 11.

When the hole transport region includes a hole injection layer, the holeinjection layer may be formed on the first electrode 11 by using one ormore suitable methods, for example, vacuum deposition, spin coating,casting, and/or Langmuir-Blodgett (LB) deposition.

When the hole injection layer is formed by vacuum deposition, thedeposition conditions may vary according to a material that is used toform the hole injection layer, and the structure and thermalcharacteristics of the hole injection layer. For example, the depositionconditions may include a deposition temperature in a range of about 100°C. to about 500° C., a vacuum pressure in a range about 10⁻⁸ torr toabout 10-3 torr, and a deposition rate in a range of about 0.01 Å/sec toabout 100 Å/sec.

When the hole injection layer is formed using spin coating, the coatingconditions may vary according to a material that is used to form thehole injection layer, and the structure and thermal characteristics ofthe hole injection layer. For example, the coating speed may be in arange of about 2,000 rpm to about 5,000 rpm, and the temperature atwhich a heat treatment is performed to remove a solvent after coatingmay be in a range of about 80° C. to about 200° C.

Conditions for forming a hole transport layer and an electron blockinglayer may be understood by referring to conditions for forming the holeinjection layer.

The hole transport region may include m-MTDATA, TDATA, 2-TNATA, NPB,β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated-NPB, TAPC, HMTPD,4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA),polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound representedby Formula 201, a compound represented by Formula 202, or a combinationthereof:

wherein, in Formula 201, Ar₁₀₁ and Ar₁₀₂ may each independently be aphenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anacenaphthylene group, a fluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, or a pentacenylene group, each unsubstituted or substituted withdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, or acombination thereof.

In Formula 201, xa and xb may each independently be an integer from 0 to5, or 0, 1, or 2. For example, xa may be 1, and xb may be 0.

In Formulae 201 and 202, R₁₀₁ to R₁₀₈, R₁₁₁ to R₁₁₉, and R₁₂₁ to R₁₂₄may each independently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₁₀ alkyl group (for example, a methyl group, an ethyl group, apropyl group, a butyl group, pentyl group, a hexyl group, etc.), or aC₁-C₁₀ alkoxy group (for example, a methoxy group, an ethoxy group, apropoxy group, a butoxy group, a pentoxy group, etc.);

a C₁-C₁₀ alkyl group or a C₁-C₁₀ alkoxy group, each unsubstituted orsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, or a combination thereof; or

a C₁-C₁₀ alkyl group or a C₁-C₁₀ alkoxy group, each unsubstituted orsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, or a combination thereof.

In Formula 201, R₁₀₉ may be a phenyl group, a naphthyl group, ananthracenyl group, or a pyridinyl group, each unsubstituted orsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, anaphthyl group, an anthracenyl group, a pyridinyl group, or acombination thereof.

In one or more embodiments, the compound represented by Formula 201 maybe represented by Formula 201A:

wherein R₁₀₁, R₁₁₁, R₁₁₂, and R₁₀₉ in Formula 201A may be understood byreferring to the description provided herein.

For example, the hole transport region may include one of Compounds HT1to HT20 or a combination thereof:

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When thehole transport region includes at least one of a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 10,000 Å, for example, about 100 Åto about 1,000 Å, and a thickness of the hole transport layer may be ina range of about 50 Å to about 2,000 Å, for example, about 100 Å toabout 1,500 Å. When the thicknesses of the hole transport region, thehole injection layer, and the hole transport layer are within theseranges, satisfactory hole transporting characteristics may be obtainedwithout a substantial increase in driving voltage.

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant. Thep-dopant may include a quinone derivative, a metal oxide, a cyanogroup-containing compound, or a combination thereof. For example, thep-dopant may be: a quinone derivative, such as tetracyanoquinodimethane(TCNQ), 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane(F4-TCNQ), or F6-TCNNQ; a metal oxide, such as tungsten oxide andmolybdenum oxide; a cyano group-containing compound, such as CompoundHT-D1; or a combination thereof.

The hole transport region may further include a buffer layer.

The buffer layer may compensate for an optical resonance distanceaccording to a wavelength of light emitted from the emission layer, andthus, efficiency of a formed organic light-emitting device may beimproved.

Meanwhile, when the hole transport region includes an electron blockinglayer, a material for forming the electron blocking layer may include amaterial that is used in the hole transport region as described above, ahost material described below, or a combination thereof. For example,when the hole transport region includes an electron blocking layer, amaterial for forming the electron blocking layer may include mCPdescribed below.

Then, an emission layer may be formed on the hole transport region byvacuum deposition, spin coating, casting, LB deposition, or the like.When the emission layer is formed by vacuum deposition or spin coating,the deposition or coating conditions may be similar to those applied informing the hole injection layer although the deposition or coatingconditions may vary according to a material that is used to form thehole transport layer.

The emission layer may include a host and a dopant, and the dopant mayinclude the organometallic compound represented by Formula 1 asdescribed herein.

The host may include TPBi, TBADN, ADN (also referred to as “DNA”), CBP,CDBP, TCP, mCP, Compound H50, Compound H51, Compound H52, or acombination thereof:

In one or more embodiments, an amount of the host in the emission layermay be greater than an amount of the at least one organometalliccompound in the emission layer, based on weight.

When the organic light-emitting device is a full-color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, and/or a blue emission layer. Inone or more embodiments, due to a stacked structure including a redemission layer, a green emission layer, and/or a blue emission layer,the emission layer may emit white light.

When the emission layer includes a host and a dopant, an amount of thedopant may be in a range of about 0.01 parts by weight to about 15 partsby weight based on 100 parts by weight of the host.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within these ranges, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

Then, an electron transport region is arranged on the emission layer.

The electron transport region may include a hole blocking layer, anelectron transport layer, an electron injection layer, or a combinationthereof.

For example, the electron transport region may have a hole blockinglayer/electron transport layer/electron injection layer structure, or anelectron transport layer/electron injection layer structure. Theelectron transport layer may have a single-layered structure or amulti-layered structure including two or more different materials.

Conditions for forming the hole blocking layer, the electron transportlayer, and the electron injection layer which constitute the electrontransport region may be understood by referring to the conditions forforming the hole injection layer.

When the electron transport region includes a hole blocking layer, thehole blocking layer may include, for example, BCP, Bphen, BAIq, or acombination thereof:

A thickness of the hole blocking layer may be in a range of about 20 Åto about 1,000 Å, for example, about 30 Å to about 600 Å. When athickness of the hole blocking layer is within these ranges, excellenthole blocking characteristics may be obtained without a substantialincrease in driving voltage.

In one or more embodiments, the electron transport layer may includeBCP, Bphen, TPBi, Alq₃, BAIq, TAZ, NTAZ, or a combination thereof:

In one or more embodiments, the electron transport layer may include oneof Compounds ET1 to ET25, or a combination thereof:

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within these ranges,satisfactory electron transport characteristics may be obtained withouta substantial increase in driving voltage.

The electron transport layer may further include, in addition to thematerials described above, a metal-containing material.

The metal-containing material may include a Li complex. The Li complexmay include, for example, Compound ET-D1 or ET-D2:

The electron transport region may include an electron injection layerthat facilitates the flow of electrons from the second electrode 19thereinto.

The electron injection layer may include LiF, NaCl, CsF, Li₂O, BaO, or acombination thereof.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, and, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within these ranges,satisfactory electron injection characteristics may be obtained withouta substantial increase in driving voltage.

The second electrode 19 is arranged on the organic layer 15. The secondelectrode 19 may be a cathode. A material for forming the secondelectrode 19 may include metal, an alloy, an electrically conductivecompound, or a combination thereof, which have a relatively low workfunction. For example, the material for forming the second electrode 19may include lithium (Li), magnesium (Mg), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), ormagnesium-silver (Mg—Ag). To manufacture a top-emission typelight-emitting device, a transmissive electrode formed using ITO or IZOmay be used as the second electrode 19.

Hereinbefore, one or more embodiments of the organic light-emittingdevice have been described with reference to the FIGURE, but embodimentsof the present disclosure are not limited thereto.

According to another aspect, the organic light-emitting device may beincluded in an electronic apparatus. Thus, another aspect of the presentdisclosure provides an electronic apparatus including the organiclight-emitting device. The electronic apparatus may include, forexample, a display, an illumination, a sensor, a mobile phone, and thelike.

Another aspect of the present disclosure provides a diagnosticcomposition including at least one organometallic compound representedby Formula 1.

The organometallic compound represented by Formula 1 may provide highluminescence efficiency. Accordingly, the diagnostic compositionincluding the organometallic compound may have high diagnosticefficiency.

The diagnostic composition may be used in various applications includinga diagnosis kit, a diagnosis reagent, a biosensor, and a biomarker.

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched saturated aliphatic hydrocarbons monovalent group having 1 to60 carbon atoms, and the term “C₁-C₆₀ alkylene group” as used hererefers to a divalent group having the same structure as the C₁-C₆₀ alkylgroup.

Examples of the C₁-C₆₀ alkyl group, the C₁-C₂₀ alkyl group, and/or theC₁-C₁₀ alkyl group are a methyl group, an ethyl group, an n-propylgroup, an isopropyl group, an n-butyl group, a sec-butyl group, anisobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentylgroup, a neopentyl group, an isopentyl group, a sec-pentyl group, a3-pentyl group, a sec-isopentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decyl group, an isodecyl group, a sec-decyl group, or a tert-decylgroup, each unsubstituted or substituted with a methyl group, an ethylgroup, an n-propyl group, an isopropyl group, an n-butyl group, asec-butyl group, an isobutyl group, a tert-butyl group, an n-pentylgroup, a tert-pentyl group, a neopentyl group, an isopentyl group, asec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexylgroup, an isohexyl group, a sec-hexyl group, a tert-hexyl group, ann-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, or a combination thereof. Forexample, Formula 9-33 is a branched C₆ alkyl group, for example, atert-butyl group that is substituted with two methyl groups.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and examples thereof are a methoxy group, an ethoxy group, a propoxygroup, a butoxy group, and a pentoxy group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbongroup formed by substituting at least one carbon-carbon double bond inthe middle or at the terminus of the C₂-C₆₀ alkyl group, and examplesthereof are an ethenyl group, a propenyl group, and a butenyl group. Theterm “C₂-C₆₀ alkenylene group” as used herein refers to a divalent grouphaving the same structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbongroup formed by substituting at least one carbon-carbon triple bond inthe middle or at the terminus of the C₂-C₆₀ alkyl group, and examplesthereof are an ethynyl group and a propynyl group. The term “C₂-C₆₀alkynylene group” as used herein refers to a divalent group having thesame structure as the C₂-C₆₀ alkynyl group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentsaturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and theterm “C₃-C₁₀ cycloalkylene group” as used herein refers to a divalentgroup having the same structure as the C₃-C₁₀ cycloalkyl group.

Examples of the term C₃-C₁₀ cycloalkyl group are a cyclopropyl group, acyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a bicyclo[1.1.1]pentylgroup, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl(norbornanyl)group, and, a bicyclo[2.2.2]octyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to amonocyclic group that includes at least one hetero atom selected from N,O, P, Si, S, Se, B, and Ge as a ring-forming atom and 1 to 10 carbonatoms, and the term “C₁-C₁₀ heterocycloalkylene group” as used hereinrefers to a divalent group having the same structure as the C₁-C₁₀heterocycloalkyl group.

Examples of the C₁-C₁₀ heterocycloalkyl group are a silolanyl group, asilinanyl group, tetrahydrofuranyl group, a tetrahydro-2H-pyranyl group,and a tetrahydrothiophenyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to amonovalent cyclic group that has 3 to 10 carbon atoms and at least onecarbon-carbon double bond in the ring thereof and no aromaticity, andexamples thereof are a cyclopentenyl group, a cyclohexenyl group, and acycloheptenyl group. The term “C₃-C₁₀ cycloalkenylene group” as usedherein refers to a divalent group having the same structure as theC₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group that has at least one hetero atom selectedfrom N, O, P, Si, S, Se, B, and Ge as a ring-forming atom, 1 to 10carbon atoms, and at least one carbon-carbon double bond in its ring.Examples of the C₁-C₁₀ heterocycloalkenyl group are a 2,3-dihydrofuranylgroup and a 2,3-dihydrothiophenyl group. The term “C₁-C₁₀heterocycloalkenylene group” as used herein refers to a divalent grouphaving the same structure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms, andthe term “C₆-C₆₀ arylene group” as used herein refers to a divalentgroup having a carbocyclic aromatic system having 6 to 60 carbon atoms.Examples of the C₆-C₆₀ aryl group are a phenyl group, a naphthyl group,an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and achrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene groupeach include two or more rings, the two or more rings may be fused toeach other.

The term “C₇-C₀ alkylaryl group” as used herein refers to a C₆-C₆₀ arylgroup substituted with at least one C₁-C₆₀ alkyl group.

The term “C₁-C₆ heteroaryl group” as used herein refers to a monovalentgroup having at least one hetero atom selected from N, O, P, Si, S, Se,B, and Ge as a ring-forming atom and a cyclic aromatic system having 1to 60 carbon atoms, and the term “C₁-C₆₀ heteroarylene group” as usedherein refers to a divalent group having at least one hetero atomselected from N, O, P, Si, S, Se, B, and Ge as a ring-forming atom and acarbocyclic aromatic system having 1 to 60 carbon atoms. Examples of theC₁-C₆₀ heteroaryl group are a pyridinyl group, a pyrimidinyl group, apyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinylgroup, and an isoquinolinyl group. When the C₆-C₆₀ heteroaryl group andthe C₆-C₆₀ heteroarylene group each include two or more rings, the twoor more rings may be fused to each other.

The term “C₂-C₆₀ alkylheteroaryl group” as used herein refers to aC₁-C₆₀ heteroaryl group substituted with at least one C₁-C₆₀ alkylgroup.

The term “C₆-C₆₀ aryloxy group” as used herein indicates —OA₁₀₂ (whereinA₁₀₂ is the C₆-C₆₀ aryl group), the term “C₆-C₆₀ arylthio group” as usedherein indicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group), and theterm “C₁-C₆₀ alkylthio group” indicates —SA₁₀₄ (wherein A₁₀₄ is theC₁-C₆₀ alkyl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group (for example, having 8 to 60 carbonatoms) having two or more rings condensed to each other, only carbonatoms as ring-forming atoms, and no aromaticity in its entire molecularstructure. An example of the monovalent non-aromatic condensedpolycyclic group is a fluorenyl group. The term “divalent non-aromaticcondensed polycyclic group” as used herein refers to a divalent grouphaving the same structure as the monovalent non-aromatic condensedpolycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group (for example, having 1 to 60carbon atoms) having two or more rings condensed to each other, aheteroatom selected from N, O, P, Si, S, Se, B, and Ge, other thancarbon atoms, as a ring-forming atom, and no aromaticity in its entiremolecular structure. An example of the monovalent non-aromatic condensedheteropolycyclic group is a carbazolyl group. The term “divalentnon-aromatic condensed heteropolycyclic group” as used herein refers toa divalent group having the same structure as the monovalentnon-aromatic condensed heteropolycyclic group.

The term “C₅-C₃₀ carbocyclic group” as used herein refers to a saturatedor unsaturated cyclic group having, as a ring-forming atom, 5 to 30carbon atoms only. The C₅-C₃₀ carbocyclic group may be a monocyclicgroup or a polycyclic group.

Examples of the “C₅-C₃₀carbocyclic group (unsubstituted or substitutedwith at least one R_(10a))” are an adamantane group, a norbornene group,a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, abicyclo[2.2.1]heptane(norbornane) group, a bicyclo[2.2.2]octane group, acyclopentane group, a cyclohexane group, a cyclohexene group, a benzenegroup, a naphthalene group, an anthracene group, a phenanthrene group, atriphenylene group, a pyrene group, a chrysene group, a1,2,3,4-tetrahydronaphthalene group, a cyclopentadiene group, and afluorene group, each unsubstituted or substituted with at least oneR_(10a) as defined herein.

The term “C₁-C₃₀ heterocyclic group” as used herein refers to asaturated or unsaturated cyclic group having, as a ring-forming atom, atleast one heteroatom selected from N, O, P, Si, Se, Ge, B, and S otherthan 1 to 30 carbon atoms. The C₁-C₆₀ heterocyclic group may be amonocyclic group or a polycyclic group.

Examples of the “C₁-C₃₀ heterocyclic group (unsubstituted or substitutedwith at least one R_(10a))” are a thiophene group, a furan group, apyrrole group, a silole group, borole group, a phosphole group, aselenophene group, a germole group, a benzothiophene group, a benzofurangroup, an indole group, a benzosilole group, a benzoborole group, abenzophosphole group, a benzoselenophene group, a benzogermole group, adibenzothiophene group, a dibenzofuran group, a carbazole group, adibenzosilole group, a dibenzoborole group, a dibenzophosphole group, adibenzoselenophene group, a dibenzogermole group, a dibenzothiophene5-oxide group, a 9H-fluorene-9-one group, a dibenzothiophene 5,5-dioxidegroup, an azabenzothiophene group, an azabenzofuran group, an azaindolegroup, an azaindene group, an azabenzosilole group, an azabenzoborolegroup, an azabenzophosphole group, an azabenzoselenophene group, anazabenzogermole group, an azadibenzothiophene group, an azadibenzofurangroup, an azacarbazole group, an azafluorene group, an azadibenzosilolegroup, an azadibenzoborole group, an azadibenzophosphole group, anazadibenzoselenophene group, an azadibenzogermole group, anazadibenzothiophene 5-oxide group, an aza-9H-fluorene-9-one group, anazadibenzothiophene 5,5-dioxide group, a pyridine group, a pyrimidinegroup, a pyrazine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a quinoxaline group, aquinazoline group, a phenanthroline group, a pyrazole group, animidazole group, a triazole group, an oxazole group, an isooxazolegroup, a thiazole group, an isothiazole group, an oxadiazole group, athiadiazole group, a benzopyrazole group, a benzimidazole group, abenzoxazole group, a benzothiazole group, a benzoxadiazole group, abenzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, and a5,6,7,8-tetrahydroquinoline group, each unsubstituted or substitutedwith at least one R_(10a) as disclosed herein.

Examples of the terms “C₅-C₃₀ carbocyclic group” and “C₁-C₃₀heterocyclic group” as used herein may include i) a first ring, ii) asecond ring, iii) a condensed cyclic group in which two or more firstrings are condensed with each other, iv) a condensed cyclic group inwhich two or more second rings are condensed with each other, or v) acondensed cyclic group in which at least one first ring is condensedwith at least one second ring, the first ring may be a cyclopentanegroup, a cyclopentadiene group, a furan group, a thiophene group, apyrrole group, a silole group, a germole group, a borole group, aselenophene group, a phosphole group, an oxazole group, an oxadiazolegroup, an oxatriazole group, a thiazole group, a thiadiazole group, athiatriazole group, a pyrazole group, an imidazole group, a triazolegroup, a tetrazole group, an azasilole group, an azagermole group, anazaborole group, an azaselenophene group, or an azaphosphole group, andthe second ring may be an adamantane group, a norbornane group (abicyclo[2.2.1]heptane group), a norbornene group, abicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, abicyclo[2.2.2]octane group, a cyclohexane group, a cyclohexene group, abenzene group, a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, or a triazine group.

The terms “fluorinated C₁-C₆₀ alkyl group (or a fluorinated C₁-C₂₀ alkylgroup or the like)”, “fluorinated C₃-C₁₀ cycloalkyl group”, “fluorinatedC₁-C₁₀ heterocycloalkyl group,” and “fluorinated phenyl group”respectively indicate a C₁-C₆₀ alkyl group (or a C₁-C₂₀ alkyl group orthe like), a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group,and a phenyl group, each substituted with at least one fluoro group(—F). For example, the “fluorinated C₁ alkyl group (that is, thefluorinated methyl group)” may include —CF₃, —CF₂H, and —CFH₂. The“fluorinated C₁-C₆₀ alkyl group (or, a fluorinated C₁-C₂₀ alkyl group,or the like)”, “the fluorinated C₃-C₁₀ cycloalkyl group”, “thefluorinated C₁-C₁₀ heterocycloalkyl group”, or “the fluorinated a phenylgroup” may be i) a fully fluorinated C₁-C₆₀ alkyl group (or, a fullyfluorinated C₁-C₂₀ alkyl group or the like), a fully fluorinated C₃-C₁₀cycloalkyl group, a fully fluorinated C₁-C₁₀ heterocycloalkyl group, ora fully fluorinated phenyl group, wherein, in each group, all hydrogensincluded therein are each substituted with a fluoro group, or ii) apartially fluorinated C₁-C₆₀ alkyl group (or, a partially fluorinatedC₁-C₂₀ alkyl group or the like), a partially fluorinated C₃-C₁₀cycloalkyl group, a partially fluorinated C₁-C₁₀ heterocycloalkyl group,or a partially fluorinated phenyl group, wherein, in each group, allhydrogens included therein are not substituted with a fluoro group.

The terms “deuterated C₁-C₆₀ alkyl group (or a deuterated C₁-C₂₀ alkylgroup or the like)”, “deuterated C₃-C₁₀ cycloalkyl group”, “deuteratedC₁-C₁₀ heterocycloalkyl group,” and “deuterated phenyl group”respectively indicate a C₁-C₆₀ alkyl group (or a C₁-C₂₀ alkyl group orthe like), a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group,and a phenyl group, each substituted with at least one deuterium. Forexample, the “deuterated C₁ alkyl group (that is, the deuterated methylgroup)” may include —CD₃, —CD₂H, and —CDH₂, and examples of the“deuterated C₃-C₁₀ cycloalkyl group” are Formula 10-501 and the like.The “deuterated C₁-C₆₀ alkyl group (or the deuterated C₁-C₂₀ alkyl groupor the like)”, “the deuterated C₃-C₁₀ cycloalkyl group”, “the deuteratedC₁-C₁₀ heterocycloalkyl group”, or “the deuterated phenyl group” may bei) a fully deuterated C₁-C₆₀ alkyl group (or a fully deuterated C₁-C₂₀alkyl group or the like), a fully deuterated C₃-C₁₀ cycloalkyl group, afully deuterated C₁-C₁₀ heterocycloalkyl group, or a fully deuteratedphenyl group, in which, in each group, all hydrogens included thereinare each substituted with deuterium, or ii) a partially deuteratedC₁-C₆₀ alkyl group (or, a partially deuterated C₁-C₂₀ alkyl group or thelike), a partially deuterated C₃-C₁₀ cycloalkyl group, a partiallydeuterated C₁-C₁₀ heterocycloalkyl group, or a partially deuteratedphenyl group, in which, in each group, all hydrogens included thereinare not substituted with deuterium.

The term “(C₁-C₂₀ alkyl) ‘X’ group” as used herein refers to a ‘X’ groupthat is substituted with at least one C₁-C₂₀ alkyl group. For example,the term “(C₁-C₂₀ alkyl)C₃-C₁₀ cycloalkyl group” as used herein refersto a C₃-C₁₀ cycloalkyl group substituted with at least one C₁-C₂₀ alkylgroup, and the term “(C₁-C₂₀ alkyl)phenyl group” as used herein refersto a phenyl group substituted with at least one C₁-C₂₀ alkyl group. Anexample of a (C₁ alkyl) phenyl group is a toluyl group.

The terms “an azaindole group, an azabenzoborole group, anazabenzophosphole group, an azaindene group, an azabenzosilole group, anazabenzogermole group, an azabenzothiophene group, anazabenzoselenophene group, an azabenzofuran group, an azacarbazolegroup, an azadibenzoborole group, an azadibenzophosphole group, anazafluorene group, an azadibenzosilole group, an azadibenzogermolegroup, an azadibenzothiophene group, an azadibenzoselenophene group, anazadibenzofuran group, an azadibenzothiophene 5-oxide group, anaza-9H-fluorene-9-one group, and an azadibenzothiophene 5,5-dioxidegroup” respectively refer to heterocyclic groups having the samebackbones as “an indole group, a benzoborole group, a benzophospholegroup, an indene group, a benzosilole group, a benzogermole group, abenzothiophene group, a benzoselenophene group, a benzofuran group, acarbazole group, a dibenzoborole group, a dibenzophosphole group, afluorene group, a dibenzosilole group, a dibenzogermole group, adibenzothiophene group, a dibenzoselenophene group, a dibenzofurangroup, a dibenzothiophene 5-oxide group, a 9H-fluorene-9-one group, adibenzothiophene 5,5-dioxide group,” in which, in each group, at leastone carbon selected from ring-forming carbon atoms is substituted with anitrogen atom.

Substituents of the substituted C₅-C₃₀carbocyclic group, the substitutedC₂-C₃₀ heterocyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₁-C₆₀ alkylthiogroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₇-C₀ alkylaryl group, the substituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀ arylthio group, the substitutedC₁-C₆₀ heteroaryl group, the substituted C₂-C₆₀ alkyl heteroaryl group,the substituted monovalent non-aromatic condensed polycyclic group, andthe substituted monovalent non-aromatic condensed heteropolycyclic groupmay each independently be: deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, or a C₁-C₆₀ alkylthio group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₀ alkoxy group, or a C₁-C₆₀alkylthio group, each substituted with deuterium, —F, —CI, —Br, —I,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkylaryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a C₂-C₆₀ alkyl heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅),—B(Q₁₆)(Q₁₇), —P(═O)(Q₁₈)(Q₁₉), —P(Q₁₈)(Q₁₉), or a combination thereof;a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₇-C₆₀ alkyl aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, or amonovalent non-aromatic condensed heteropolycyclic group, eachunsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₁-C₆₀ alkylthio group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₀ alkyl aryl group,a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₀ heteroarylgroup, a C₂-C₆₀ alkyl heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, a monovalent non-aromatic condensedheteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇),—P(═O)(Q₂₈)(Q₂₉), —P(Q₂₈)(Q₂₉), or a combination thereof; —N(Q₃₁)(Q₃₂),—Si(Q₃₃)(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇), —P(═O)(Q₃₈)(Q₃₉), or —P(Q₃₈)(Q₃₉); ora combination thereof,

In the present specification, Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁to Q₃₉ may each independently be: hydrogen; deuterium; —F; —C₁; —Br; —I;a hydroxyl group; a cyano group; a nitro group; an amidino group; ahydrazine group; a hydrazone group; a carboxylic acid group or a saltthereof; a sulfonic acid group or a salt thereof; a phosphoric acidgroup or a salt thereof; a C₁-C₆₀ alkyl group unsubstituted orsubstituted with deuterium, —F, a cyano group, a C₁-C₆₀ alkyl group, aC₆-C₆₀ aryl group, a deuterated C₆-C₆₀ aryl group, a fluorinated C₆-C₆₀aryl group, or a combination thereof; a C₂-C₆₀ alkenyl group; a C₂-C₆₀alkynyl group; a C₁-C₆₀ alkoxy group; a C₃-C₁₀ cycloalkyl group; aC₁-C₁₀ heterocycloalkyl group; a C₃-C₁₀ cycloalkenyl group; a C₁-C₁₀heterocycloalkenyl group; a C₆-C₆₀ aryl group or a C₁-C₆₀ heteroarylgroup, each unsubstituted or substituted with deuterium, —F, a cyanogroup, a C₁-C₆₀ alkyl group, a deuterated C₁-C₆₀ alkyl group, afluorinated C₁-C₆₀ alkyl group, a C₁-C₆₀ aryl group, a deuterated C₆-C₆₀aryl group, a fluorinated C₆-C₆₀ aryl group, or a combination thereof; aC₆-C₆₀ aryloxy group; a C₆-C₆₀ arylthio group; a monovalent non-aromaticcondensed polycyclic group; or a monovalent non-aromatic condensedheteropolycyclic group.

For example, Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ may eachay each independently be:

—CH₃, —CD₃, —CD₂H, —CDH₂, —CH₂CH₃, —CH₂CD₃, —CH₂CD₂H, —CH₂CDH₂, —CHDCH₃,—CHDCD₂H, —CHDCDH₂, —CHDCD₃, —CD₂CD₃, —CD₂CD₂H, or —CD₂CDH₂; or

an n-propyl group, an isopropyl group, an n-butyl group, a sec-butylgroup, an isobutyl group, a tert-butyl group, an n-pentyl group, atert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentylgroup, 3-pentyl group, a sec-isopentyl group, a phenyl group, a biphenylgroup, or a naphthyl group, each unsubstituted or substituted withdeuterium, a C₁-C₂₀ alkyl group, a phenyl group, or a combinationthereof.

Hereinafter, a compound and an organic light-emitting device accordingto one or more embodiments are described in further detail withreference to Synthesis Example and Examples. However, the organiclight-emitting device is not limited thereto. The wording “B was usedinstead of A” used in describing Synthesis Examples means that an amountof A used was identical to an amount of B used, in terms of a molarequivalent.

EXAMPLES Synthesis Example 1 (Compound 171)

Synthesis of Compound 171A

4-isobutyl-2-phenyl-5-(trimethylsilyl)pyridine) (7.9 grams (g), 27.8millimoles (mmol)) and iridium chloride hydrate (IrCl₃.(H₂O)_(n)) (4.4g, 12.6 mmol) were mixed with 120 mL of ethoxyethanol and 40 mL ofdeionized water, and the mixture was stirred at reflux for 24 hours.Then, the reaction temperature was reduced to room temperature. Theresulting solid produced therefrom was separated by filtration,sufficiently washed with water/methanol/hexane in the stated order, anddried in a vacuum oven, so as to obtain 7.6 g (yield of 76%) of Compound171A.

Synthesis of Compound 171B

Compound 171A (3.3 g, 2.1 mmol) was mixed with 90 mL of methylenechloride, and a mixture containing AgOTf (silver triflate) (1.1 g, 4.1mmol) and 30 mL of methanol was added thereto. Afterwards, the resultantmixture was stirred at room temperature for 18 hours while blocking thelight with aluminum foil. The resultant was filtered using Celite toremove a solid formed therefrom and filtered under reduced pressure tothereby obtain a solid (Compound 171B). The solid was used in the nextreaction without further purification.

Synthesis of Compound 171

Compound 171B (4.0 g, 4.1 mmol) and2-(dibenzo[b,d]furan-4-yl)-4-(2-phenylpropan-2-yl)pyridine (1.6 g, 4.5mmol) were mixed with 40 mL of ethanol, and the mixture was stirred atreflux for 18 hours. Then, the reaction temperature was lowered. Solventwas removed from the resultant mixture thus obtained under reducedpressure and subjected to column chromatography (eluent: methylenechloride (MC) and hexane), so as to obtain 1.5 g (yield of 33%) ofCompound 171. The compound was identified by Mass and HPLC.

High resolution mass spectrometry—(Matrix Assisted Laser DesorptionIonization) (HRMS(MALDI)) calcd. for C₆₂H₆₈IrN₃OSi₂: m/z 1119.4530Found: 1119.4523.

Synthesis Example 2 (Compound 1032)

Synthesis of Compound 1032A

6.9 g (yield of 69%) of Compound 1032A was obtained in the same manneras used to obtain Compound 171A of Synthesis Example 1, except that2-(4-(methyl-d3)phenyl)-4-(propan-2-yl-2-d)-5-(trimethylsilyl)pyridinewas used instead of 4-isobutyl-2-phenyl-5-(trimethylsilyl)pyridine.

Synthesis of Compound 1032B

Compound 1032B was obtained in the same manner as used to obtainCompound 171B of Synthesis Example 1, except that Compound 1032A wasused instead of Compound 171A. Compound 1032B thus obtained was used inthe next reaction without further purification.

Synthesis of Compound 1032

0.9 g (yield of 27%) of Compound 1032 was obtained in the same manner asused to obtain Compound 171 of Synthesis Example 1, except that Compound1032B was used instead of Compound 171B and that2-(phenanthro[3,2-b]benzofuran-11-yl)-4-(phenylmethyl-d2)pyridine wasused instead of2-(dibenzo[b,d]furan-4-yl)-4-(2-phenylpropan-2-yl)pyridine. The compoundwas identified by mass spectrometry (MS) and high-pressure liquidchromatography (HPLC).

HRMS(MALDI) calcd for C₆₈H₅₈D₁₀IrN₃OSi₂: m/z 1201.5158 Found: 1201.5164.

Synthesis Example 3 (Compound 1485)

Synthesis of Compound 1485A

8.1 g (yield of 81%) of Compound 1485A was obtained in the same manneras used to obtain Compound 171A of Synthesis Example 1, except that5-(methyl-d3)-2-(4-(methyl-d3)phenyl)-4-(propan-2-yl-2-d)pyridine wasused instead of 4-isobutyl-2-phenyl-5-(trimethylsilyl)pyridine.

Synthesis of Compound 1485B

Compound 1485B was obtained in the same manner as used to obtainCompound 171B of Synthesis Example 1, except that Compound 1485A wasused instead of Compound 171A. Compound 1485B thus obtained was used inthe next reaction without further purification.

Synthesis of Compound 1485

1.2 g (yield of 36%) of Compound 1485 was obtained in the same manner asused to obtain Compound 171 of Synthesis Example 1, except that Compound1485B was used instead of Compound 171B and that8-(4-(2,2-dimethylpropyl-1,1-d2)pyridin-2-yl)-2-(2-phenylpropan-2-yl)benzofuro[2,3-b]pyridinewas used instead of2-(dibenzo[b,d]furan-4-yl)-4-(2-phenylpropan-2-yl)pyridine. The compoundwas identified by MS and HPLC.

HRMS(MALDI) calcd for C₆₂H₄₉D₁₆IrN₄O: m/z 1090.5792 Found: 1090.5788.

Synthesis Example 4 (Compound 2051)

Synthesis of Compound 2051A

6.6 g (yield of 66%) of Compound 2051A was obtained in the same manneras used to obtain Compound 171A of Synthesis Example 1, except that2-(2-fluoro-3-(methyl-d3)phenyl)-5-(methyl-d3)-4-(1-phenylethyl-1-d)pyridinewas used instead of 4-isobutyl-2-phenyl-5-(trimethylsilyl)pyridine.

Synthesis of Compound 2051B

Compound 2051B was obtained in the same manner as used to obtainCompound 171B of Synthesis Example 1, except that Compound 2051A wasused instead of Compound 171A. Compound 2051B thus obtained was used inthe next reaction without further purification.

Synthesis of Compound 2051

1.3 g (yield of 29%) of Compound 2051 was obtained in the same manner asused to obtain Compound 171 of Synthesis Example 1, except that Compound2051B was used instead of Compound 171B and that2-(dibenzo[b,d]furan-4-yl)-4-(propan-2-yl-2-d)pyridine was used insteadof 2-(dibenzo[b,d]furan-4-yl)-4-(2-phenylpropan-2-yl)pyridine. Thecompound was identified by Mass and HPLC.

HRMS(MALDI) calcd for C₆₂H₃₉D₁₅F₂IrN₃O: m/z 1102.4806 Found: 1102.4801.

Synthesis Example 5 (Compound 2111)

Synthesis of Compound 2111A

7.9 g (yield of 79%) of Compound 2111A was obtained in the same manneras used to obtain Compound 171A of Synthesis Example 1, except that2-(4-(methyl-d3)phenyl)-4-(phenylmethyl-d2)-5-(trimethylsilyl)pyridinewas used instead of 4-isobutyl-2-phenyl-5-(trimethylsilyl)pyridine.

Synthesis of Compound 2111B

Compound 2111B was obtained in the same manner as used to obtainCompound 171B of Synthesis Example 1, except that Compound 2111A wasused instead of Compound 171A. Compound 2111B thus obtained was used inthe next reaction without further purification.

Synthesis of Compound 2111

1.5 g (yield of 40%) of Compound 2111 was obtained in the same manner asused to obtain Compound 171 of Synthesis Example 1, except that Compound2111B was used instead of Compound 171B and that2-(dibenzo[b,d]furan-4-yl)-4-(2,2-dimethylpropyl-1,1-d2)pyridine wasused instead of2-(dibenzo[b,d]furan-4-yl)-4-(2-phenylpropan-2-yl)pyridine. The compoundwas identified by Mass and HPLC.

HRMS(MALDI) calcd for C₆₆H₅₆D₁₂IrN₃OSi₂: m/z 1179.5283 Found: 1179.5288.

Synthesis Example 6 (Compound 2543)

Synthesis of Compound 2543A

5.4 g (yield of 54%) of Compound 2543A was obtained in the same manneras used to obtain Compound 171A of Synthesis Example 1, except that2-(dibenzo[b,d]furan-4-yl)-4-(2,2-dimethylpropyl-1,1-d2)pyridine wasused instead of 4-isobutyl-2-phenyl-5-(trimethylsilyl)pyridine.

Synthesis of Compound 2543B

Compound 2543B was obtained in the same manner as used to obtainCompound 171B of Synthesis Example 1, except that Compound 2543A wasused instead of Compound 171A. Compound 2543B thus obtained was used inthe next reaction without further purification.

Synthesis of Compound 2543

0.9 g (yield of 23%) of Compound 2543 was obtained in the same manner asused to obtain Compound 171 of Synthesis Example 1, except that Compound2543B was used instead of Compound 171B and that2-(4-(methyl-d3)phenyl)-4-(phenylmethyl-d2)-5-(trimethylgermyl)pyridinewas used instead of2-(dibenzo[b,d]furan-4-yl)-4-(2-phenylpropan-2-yl)pyridine. The compoundwas identified by Mass and HPLC.

HRMS(MALDI) calcd for C₆₆H₅₅D₉GeIrN₃O₂: m/z 1206.4404 Found: 1206.4414.

Example 1

A glass substrate with ITO/Ag/ITO as an anode deposited thereon to athickness of 70 Å/1,000 Å/70 Å was cut to a size of 50 millimeters(mm)×50 mm×0.5 mm, sonicated with isopropyl alcohol and pure water eachfor 5 minutes, and then cleaned by exposure to ultraviolet rays andozone for 30 minutes. Then, the resultant glass substrate was loadedonto a vacuum deposition apparatus.

2-TNATA was vacuum-deposited on the anode to form a hole injection layerhaving a thickness of 600 Å, and 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (hereinafter referred to as NPB) was vacuum-deposited on thehole injection layer to form a hole transport layer having a thicknessof 1,350 Å.

Subsequently, CBP (host) and Compound 171 (dopant) were co-deposited ata weight ratio of 98:2 on the hole transport layer to form an emissionlayer having a thickness of 400 Å.

Afterwards, BCP was vacuum-deposited on the emission layer to form ahole blocking layer having a thickness of 50 Å, Alq₃ wasvacuum-deposited on the hole blocking layer to form an electrontransport layer having a thickness of 350 Å, LiF was vacuum-deposited onthe electron transport layer to form an electron injection layer havinga thickness of 10 Å, and Mg and Ag were co-deposited at a weight ratioof 90:10 on the electron injection layer to form a cathode having athickness of 120 Å, thereby completing an organic light-emitting device.

Examples 2 to 6 and Comparative Examples A to C

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that compounds shown in Table 2 were each usedinstead of Compound 171 as a dopant in forming an emission layer.

Evaluation Example 1: Characterization of Organic Light-Emitting Device

Regarding each of the organic light-emitting devices of Examples 1 to 6and Comparative Examples A to C, the driving voltage, maximum value (%)of external quantum efficiency (EQE), and lifespan (LT₉₇)(hr.) wereevaluated, and results thereof are shown in Table 2. This evaluation wasperformed using a current-voltage meter (Keithley 2400) and a luminancemeter (Minolta Cs-1000A), and the lifespan (LT₉₇)(at 16,000 candela persquare meter (cd/m²) was evaluated by measuring, as a relative value(%), the amount of time that elapsed until luminance was reduced to 97%of the initial luminance of 100%. The compounds were provided as adopant in an emission layer.

TABLE 2 Compound Max EQE LT₉₇ (%) No. (%) (at 16,000 cd/m²) Example 1 171 25.9 100 Example 2 1032 27.4 207 Example 3 1485 26.8 113 Example 42051 26.2 108 Example 5 2111 26.5 154 Example 6 2543 27.1 193Comparative A 23.4 19 Example A Comparative B 22.8 35 Example BComparative C 21.6 23 Example C

Referring to Table 2, it was confirmed that the organic light-emittingdevices of Example 1 to 6 had improved EQE and improved lifespancharacteristics compared to the organic light-emitting devices ofComparative Examples A to C.

According to the one or more embodiments, an organometallic compound mayhave excellent electrical characteristics and heat resistance, so thatan electronic device, such as an organic light-emitting device,including the organometallic compound may have excellent EQE andexcellent lifespan characteristics. Therefore, the use of theorganometallic compound may enable the embodiment of a high-qualityorganic light-emitting device and an electron device including the same.

It should be understood that embodiments described herein should beconsidered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments. While one or more embodiments have beendescribed with reference to the FIGURES, it will be understood by thoseof ordinary skill in the art that various changes in form and detailsmay be made therein without departing from the spirit and scope of thepresent disclosure as defined by the following claims.

What is claimed is:
 1. An organometallic compound represented by Formula1:M(L₁)_(n1)(L₂)_(n2)  Formula 1 wherein, in Formula 1, M is a transitionmetal, L₁ is a ligand represented by Formula 2, n1 is 1, 2, or 3,wherein, when n1 is 2, two L₁ groups are identical to or different fromeach other, and when n1 is 3, two or more of three L₁ groups aredifferent from each other, L₂ is a monodentate ligand, a bidentateligand, a tridentate ligand, or a tetradentate ligand, n2 is 0, 1, 2, 3,or 4, wherein, when n2 is 2 or greater, two or more L₂ groups areidentical to or different from each other, and L₁ and L₂ are differentfrom each other,

wherein, in Formula 2, Y₁ and Y₂ are each independently C or N, ring CY₁and ring CY₂ are each independently a C₅-C₃₀ carbocyclic group or aC₁-C₃₀ heterocyclic group, R₁ and R₂ are each independently hydrogen,deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₁-C₆₀ alkylthio group, asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —Ge(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇),—P(═O)(Q₈)(Q₉), or —P(Q₈)(Q₉), a1 and a2 are each independently aninteger from 0 to 20, b1 and b2 are each independently an integer from 0to 20, wherein the sum of b1 and b2 is 1 or greater, Z₁ and Z₂ are eachindependently a group represented by Formula 3,

wherein, in Formula 3, Q₅₁ and Q₅₂ are each independently hydrogen,deuterium, —F, a cyano group, a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀alkylthio group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group,a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromaticcondensed polycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, Q₅₃ is a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromaticcondensed polycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, two or more of aplurality of R1 groups are optionally linked together to form a C₅-C₃₀carbocyclic group that is unsubstituted or substituted with at least oneR_(10a) or a C₁-C₃₀ heterocyclic group that is unsubstituted orsubstituted with at least one R_(10a), two or more of a plurality of R₂groups are optionally linked together to form a C₅-C₃₀ carbocyclic groupthat is unsubstituted or substituted with at least one R_(10a) or aC₁-C₃₀ heterocyclic group that is unsubstituted or substituted with atleast one R_(10a), R_(10a) is the same as described in connection withR1, * and *′ in Formula 2 each indicate a binding site to M in Formula1, * in Formula 3 indicates a binding site to a neighboring atom, inFormula 2 and Formula 3, substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₁-C₆₀ alkylthio group, the substituted C₃-C₁₀ cycloalkyl group, thesubstituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, thesubstituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, thesubstituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroarylgroup, the substituted monovalent non-aromatic condensed polycyclicgroup, and the substituted monovalent non-aromatic condensedheteropolycyclic group are each independently: deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, or a C₁-C₆₀ alkoxy group, each substituted withdeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅),—Ge(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), —P(═O)(Q₁₈)(Q₁₉), —P(Q₁₈)(Q₁₉), or acombination thereof; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, or a monovalent non-aromaticcondensed heteropolycyclic group, each unsubstituted or substituted withdeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅),—Ge(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), —P(═O)(Q₂₈)(Q₂₉), —P(Q₂₈)(Q₂₉), or acombination thereof; —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅),—Ge(Q₃₃)(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇), —P(═O)(Q₃₈)(Q₃₉), or —P(Q₃₈)(Q₃₉); ora combination thereof, and Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ toQ₃₉ are each independently: hydrogen; deuterium; —F; —C₁; —Br; —I; ahydroxyl group; a cyano group; a nitro group; an amidino group; ahydrazine group; a hydrazone group; a carboxylic acid group or a saltthereof; a sulfonic acid group or a salt thereof; a phosphoric acidgroup or a salt thereof; a C₁-C₆₀ alkyl group unsubstituted orsubstituted with deuterium, —F, a cyano group, a C₁-C₆₀ alkyl group, aC₆-C₆₀ aryl group, a deuterated C₆-C₆₀ aryl group, a fluorinated C₆-C₆₀aryl group, or a combination thereof; a C₂-C₆₀ alkenyl group; a C₂-C₆₀alkynyl group; a C₁-C₆₀ alkoxy group; a C₃-C₁₀ cycloalkyl group; aC₁-C₁₀ heterocycloalkyl group; a C₃-C₁₀ cycloalkenyl group; a C₁-C₁₀heterocycloalkenyl group; a C₆-C₆₀ aryl group or a C₁-C₆₀ heteroarylgroup, each unsubstituted or substituted with deuterium, —F, a cyanogroup, a C₁-C₆₀ alkyl group, a deuterated C₁-C₆₀ alkyl group, afluorinated C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a deuterated C₆-C₆₀aryl group, a fluorinated C₆-C₆₀ aryl group, or a combination thereof; aC₆-C₆₀ aryloxy group; a C₆-C₆₀ arylthio group; a monovalent non-aromaticcondensed polycyclic group; or a monovalent non-aromatic condensedheteropolycyclic group.
 2. The organometallic compound of claim 1,wherein ring CY₁ in Formula 2 is a pyridine group, a pyrimidine group, apyrazine group, a pyridazine group, a triazine group, a quinoline group,an isoquinoline group, a quinoxaline group, a quinazoline group, abenzoquinoline group, a benzoisoquinoline group, a benzoquinoxalinegroup, a benzoquinazoline group, a phenanthroline group, aphenanthridine group, a 5,6,7,8-tetrahydroisoquinoline group, a5,6,7,8-tetrahydroquinoline group, an azafluorene group, an azacarbazolegroup, an azadibenzofuran group, an azadibenzothiophene group, or anazadibenzosilole group.
 3. The organometallic compound of claim 1,wherein ring CY₂ in Formula 2 is a benzene group, a naphthalene group,an anthracene group, a phenanthrene group, a triphenylene group, apyrene group, a chrysene group, a 1,2,3,4-tetrahydronaphthalene group,or a group represented by Formula 2B:

wherein, in Formula 2B, X₂ is O, S, Se, or a moiety comprising N, C, orSi, ring 2B-1 and ring 2B-2 are each independently a benzene group, anaphthalene group, an anthracene group, a phenanthrene group, atriphenylene group, a pyrene group, a chrysene group, a1,2,3,4-tetrahydronaphthalene group, a pyridine group, a pyrimidinegroup, a pyrazine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a quinoxaline group, aquinazoline group, a benzoquinoline group, a benzoisoquinoline group, abenzoquinoxaline group, a benzoquinazoline group, a phenanthrolinegroup, a phenanthridine group, a 5,6,7,8-tetrahydroisoquinoline group, a5,6,7,8-tetrahydroquinoline group, an indene group, an indole group, abenzofuran group, a benzothiophene group, a benzosilole group, afluorene group, a carbazole group, a dibenzofuran group, adibenzothiophene group, a dibenzosilole group, an azaindene group, anazaindole group, an azabenzofuran group, an azabenzothiophene group, anazabenzosilole group, an azafluorene group, an azacarbazole group, anazadibenzofuran group, an azadibenzothiophene group, or anazadibenzosilole group.
 4. The organometallic compound of claim 1,wherein R₁ and R₂ in Formula 2 are each independently: hydrogen,deuterium, —F, or a cyano group; a C₁-C₂₀ alkyl group unsubstituted orsubstituted with deuterium, —F, a cyano group, a C₃-C₁₀ cycloalkylgroup, a deuterated C₃-C₁₀ cycloalkyl group, a fluorinated C₃-C₁₀cycloalkyl group, a (C₁-C₂₀ alkyl)C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a deuterated C₁-C₁₀ heterocycloalkyl group, afluorinated C₁-C₁₀ heterocycloalkyl group, a (C₁-C₂₀ alkyl)C₁-C₁₀heterocycloalkyl group, or a combination thereof; a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a phenyl group, a biphenylgroup, a naphthyl group, or a pyridinyl group, each unsubstituted orsubstituted with deuterium, —F, a cyano group, a C₁-C₂₀ alkyl group, adeuterated C₁-C₂₀ alkyl group, a fluorinated C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a deuterated C₁-C₂₀ alkoxy group, a fluorinatedC₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a deuterated C₃-C₁₀cycloalkyl group, a fluorinated C₃-C₁₀ cycloalkyl group, a (C₁-C₂₀alkyl)C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, adeuterated C₁-C₁₀ heterocycloalkyl group, a fluorinated C₁-C₁₀heterocycloalkyl group, a (C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, aphenyl group, a deuterated phenyl group, a fluorinated phenyl group, a(C₁-C₂₀ alkyl)phenyl group, a biphenyl group, a deuterated biphenylgroup, a fluorinated biphenyl group, a (C₁-C₂₀ alkyl)biphenyl group, anaphthyl group, a deuterated naphthyl group, a fluorinated naphthylgroup, a (C₁-C₂₀ alkyl)naphthyl group, a pyridinyl group, a deuteratedpyridinyl group, a fluorinated pyridinyl group, a (C₁-C₂₀alkyl)pyridinyl group, or a combination thereof; or —Si(Q₃)(Q₄)(Q₅) or—Ge(Q₃)(Q₄)(Q₅), wherein, Q₃ to Q₅ are each independently: deuterium; aC₁-C₆₀ alkyl group unsubstituted or substituted with deuterium, —F, acyano group, a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a deuteratedC₆-C₆₀ aryl group, a fluorinated C₆-C₆₀ aryl group, or a combinationthereof; or a C₆-C₆₀ aryl group or a C₁-C₆₀ heteroaryl group, eachunsubstituted or substituted with deuterium, —F, a cyano group, a C₁-C₆₀alkyl group, a deuterated C₁-C₆₀ alkyl group, a fluorinated C₁-C₆₀ alkylgroup, a C₆-C₆₀ aryl group, a deuterated C₆-C₆₀ aryl group, afluorinated C₆-C₆₀ aryl group, or a combination thereof.
 5. Theorganometallic compound of claim 1, wherein at least one R₁ in thenumber of a1 in Formula 2 is: deuterium; —F; a C₁-C₂₀ alkyl group or aC₃-C₁₀ cycloalkyl group, each unsubstituted or substituted withdeuterium, —F, C₁-C₁₀ alkyl group, or a combination thereof; a grouprepresented by —Si(Q₃)(Q₄)(Q₅); or a group represented by—Ge(Q₃)(Q₄)(Q₅).
 6. The organometallic compound of claim 1, wherein i)b1 is 1 or 2, and b2 is 0; ii) b1 is 0, and b2 is 1 or 2; or iii) b1 andb2 are each
 1. 7. The organometallic compound of claim 1, wherein atleast one of Q₅₁ and Q₅₂ in Formula 3 is each independently deuterium, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group.
 8. The organometalliccompound of claim 1, wherein at least one of Q₅₁ and Q₅₂ in Formula 3 iseach independently: deuterium; or a C₁-C₂₀ alkyl group unsubstituted orsubstituted with deuterium, —F, or a combination thereof.
 9. Theorganometallic compound of claim 1, wherein Q₅₃ in Formula 3 is a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a phenyl group, abiphenyl group, a naphthyl group, or a pyridinyl group, eachunsubstituted or substituted with deuterium, —F, a cyano group, a C₁-C₂₀alkyl group, a deuterated C₁-C₂₀ alkyl group, a fluorinated C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a deuterated C₁-C₂₀ alkoxy group, afluorinated C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a deuteratedC₃-C₁₀ cycloalkyl group, a fluorinated C₃-C₁₀ cycloalkyl group, a(C₁-C₂₀ alkyl)C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group,a deuterated C₁-C₁₀ heterocycloalkyl group, a fluorinated C₁-C₁₀heterocycloalkyl group, a (C₁-C₂₀ alkyl)C₁-C₁₀ heterocycloalkyl group, aphenyl group, a deuterated phenyl group, a fluorinated phenyl group, a(C₁-C₂₀ alkyl)phenyl group, a biphenyl group, a deuterated biphenylgroup, a fluorinated biphenyl group, a (C₁-C₂₀ alkyl)biphenyl group, anaphthyl group, a deuterated naphthyl group, a fluorinated naphthylgroup, a (C₁-C₂₀ alkyl)naphthyl group, a pyridinyl group, a deuteratedpyridinyl group, a fluorinated pyridinyl group, a (C₁-C₂₀alkyl)pyridinyl group, or a combination thereof.
 10. The organometalliccompound of claim 1, wherein in Formula 2, a group represented by

is a group represented by one of Formulae CY1(1) to CY1(16) and CY1(1)Zto CY1(38)Z:

wherein, in Formulae CY1(1) to CY1(16) and CY1(1)Z to CY1(38)Z, Y₁ isthe same as described in claim 1, R₁₁ to R₁₄ are each the same asdescribed in connection with R₁ in claim 1, provided that each of R₁₁ toR₁₄ is not hydrogen, Z₁₁ to Z₁₄ are each the same as described inconnection with Z₁ in claim 1, *′ indicates a binding site to M inFormula 1, and *″ indicates a binding site to ring CY₂ in Formula
 2. 11.The organometallic compound of claim 1, wherein in Formula 2, a grouprepresented by

is a group represented by one of Formulae CY2(1) to CY2(96) and CY2(1)Zto CY2(54)Z:

wherein, in Formula CY2(1) to CY2(96) and CY2(1)Z to CY2(54)Z, Y₂ is thesame as described in claim 1, X₂₂ is C(R_(29a))(R_(29b)), N(R_(29a)), O,S, Se, or Si(R_(29a))(R_(29b)), R₂₁ to R₂₈, R_(29a), and R_(29b) areeach the same as described in connection with R₂ in claim 1, providedthat each of R₂₁ to R₂₈ is not hydrogen, Z₂₁ to Z₂₈ are each the same asdescribed in connection with Z₂ in claim 1, * indicates a binding siteto M in Formula 1, and *″ indicates a binding site to ring CY₁ inFormula
 2. 12. The organometallic compound of claim 1, wherein inFormula 1, L₂ is a group represented by one of Formulae 4A to 4F:

wherein, in Formulae 4A to 4F, Y₁₃ is O, N, N(R₃), P(R₃)(R₄), orAs(R₃)(R₄), Y₁₄ is O, N, N(R₅), P(R₅)(R₆), or As(R₅)(R₆), T₁₁ is asingle bond, a double bond, *—C(R₃₁)(R₃₂)—*′, *—C(R₃₁)═C(R₃₂)—*′,*═C(R₃₁)—*′, *—C(R₃₁)═*′, *═C(R₃₁)—C(R₃₂)═C(R₃₃)—*′,*—C(R₃₁)═C(R₃₂)—C(R₃₃)═*′, *—N(R₃₁)—*′, or a C₅-C₃₀ carbocyclic groupunsubstituted or substituted with at least one R₃₁, d11 is an integerfrom 1 to 10, wherein, when d11 is 2 or greater, two or more T₁₁ groupsare identical to or different from each other, Y₃ and Y₄ are eachindependently C or N, T₂₁ is a single bond, a double bond, O, S, Se,C(R₅)(R₆), Si(R₅)(R₆), or N(R₅), ring CY₃ and ring CY₄ are eachindependently a C₅-C₃₀ carbocyclic group or a C₁-C₃₀ heterocyclic group,A₁ is P or As, R₃ to R₈ and R₃₁ to R₃₃ are each the same as described inconnection with R₁ in claim 1, a3 and a4 are each independently aninteger from 0 to 20, and * and *′ each indicate a binding site to M inFormula
 1. 13. The organometallic compound of claim 12, wherein inFormula 4D, a group represented by

is a group represented by one of Formulae CY3(1) to CY3(16):

wherein, in Formulae CY3(1) to CY3(16), Y₃ is the same as described inclaim 12, R₃₁ to R₃₄ are each the same as described in connection withR₃ in claim 12, provided that each of R₃₁ to R₃₄ is not hydrogen, *indicates a binding site to M in Formula 1, and *″ indicates a bindingsite to T₂₁ in Formula 4D.
 14. The organometallic compound of claim 12,wherein in Formulae 4C and 4D, a group represented by

is a group represented by one of Formulae CY4(1) to CY4(96):

wherein, in Formulae CY4(1) to CY4(96), Y₄ is the same as described inclaim 12, X₄₂ is C(R_(49a))(R_(49b)), N(R_(49a)), O, S, Se, orSi(R_(49a))(R_(49b)), R₄₁ to R₄₈, R_(49a), and R_(49b) are each the sameas described in connection with R₄ in claim 12, provided that each ofR₄₁ to R₄₈ is not hydrogen, *′ indicates a binding site to M in Formula1, and *″ indicates a binding site to a neighboring atom in Formula 4Cor a binding site to T₂₁ in Formula 4D.
 15. An organic light-emittingdevice, comprising: a first electrode; a second electrode; and anorganic layer disposed between the first electrode and the secondelectrode and comprising an emission layer, wherein the organic layercomprises at least one organometallic compound of claim
 1. 16. Theorganic light-emitting device of claim 15, wherein the first electrodeis an anode, the second electrode is a cathode, the organic layerfurther comprises a hole transport region disposed between the firstelectrode and the emission layer, and an electron transport regiondisposed between the emission layer and the second electrode, the holetransport region comprises a hole injection layer, a hole transportlayer, an electron blocking layer, a buffer layer, or a combinationthereof, and the electron transport region comprises a hole blockinglayer, an electron transport layer, an electron injection layer, or acombination thereof.
 17. The organic light-emitting device of claim 15,wherein the emission layer comprises the at least one organometalliccompound.
 18. The organic light-emitting device of claim 17, wherein theat least one organometallic compound emits green light.
 19. The organiclight-emitting device of claim 17, wherein the emission layer furthercomprises a host, and an amount of the host in the emission layer isgreater than an amount of the at least one organometallic compound inthe emission layer, based on weight.
 20. An electronic apparatus,comprising the organic light-emitting device of claim 15.